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preamp for using an SDR as a pan adapter

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AE4ED

preamp for using an SDR as a pan adapter

Good afternoon,

I have successfully connected my QSR-1 to my K3s if-out, and immediately
noticed the signal strengths showing on the QSR-1 were much weaker. I
probably have an early K3s, so the if-out signal strength is even weaker.

Any recommendations at a good preamp to use? It seems like 20db is what I
need:

73,
Fred
AE4ED
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Wes Stewart-2

Re: preamp for using an SDR as a pan adapter

I use an SDR-IQ on the i-f output on my (very) early K3S. it works fine. IIRC,
always a dubious proposition, I did the mod on my original K3 and it worked well
too without any additional amplification. I think you have another problem.

Wes N7WS

On 10/3/2019 2:01 PM, Fred Massey wrote:

> Good afternoon,
>
> I have successfully connected my QSR-1 to my K3s if-out, and immediately
> noticed the signal strengths showing on the QSR-1 were much weaker. I
> probably have an early K3s, so the if-out signal strength is even weaker.
>
> Any recommendations at a good preamp to use? It seems like 20db is what I
> need:
>
> 73,
> Fred
> AE4ED

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NS9I WI

K-POD sold

In reply to this post by AE4ED

Thanks 73 Dwight NS9I

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AE4ED

Re: preamp for using an SDR as a pan adapter

In reply to this post by Wes Stewart-2

Good afternoon Wes and all,

If I connect the antenna directly to the QSR-1, I get the same signal level
as the K3s. But, when I connect to the QSR-1 to the IF-out, the signal is
about 4 s-units less.

Any ideas...anyone?

Fred

On Thu, Oct 3, 2019 at 4:14 PM Wes <[hidden email]> wrote:

> I use an SDR-IQ on the i-f output on my (very) early K3S. it works fine.
> IIRC,
> always a dubious proposition, I did the mod on my original K3 and it
> worked well
> too without any additional amplification. I think you have another
> problem.
>
> Wes N7WS
>
> On 10/3/2019 2:01 PM, Fred Massey wrote:
> > Good afternoon,
> >
> > I have successfully connected my QSR-1 to my K3s if-out, and immediately
> > noticed the signal strengths showing on the QSR-1 were much weaker. I
> > probably have an early K3s, so the if-out signal strength is even weaker.
> >
> > Any recommendations at a good preamp to use? It seems like 20db is what
> I
> > need:
> >
> > 73,
> > Fred
> > AE4ED
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> Message delivered to [hidden email]

Don Wilhelm

Re: preamp for using an SDR as a pan adapter

Fred,

Have you looked the K3 IF Output mod?
https://ftp.elecraft.com/K3/Mod%20Notes%20Alerts/IF_Output_Buffer_Gain_Mod_Rev_A.pdf

If you don't have the 13k SMD resistor or a 1/8 watt 13k resistor, you
can order the kit from Elecraft.

73,
Don W3FPR

On 10/4/2019 1:24 PM, Fred Massey wrote:

> Good afternoon Wes and all,
>
> If I connect the antenna directly to the QSR-1, I get the same signal level
> as the K3s. But, when I connect to the QSR-1 to the IF-out, the signal is
> about 4 s-units less.
>
> Any ideas...anyone?
>
> Fred
>
> On Thu, Oct 3, 2019 at 4:14 PM Wes <[hidden email]> wrote:
>
>> I use an SDR-IQ on the i-f output on my (very) early K3S. it works fine.
>> IIRC,
>> always a dubious proposition, I did the mod on my original K3 and it
>> worked well
>> too without any additional amplification. I think you have another
>> problem.
>>
>> Wes N7WS
>>
>> On 10/3/2019 2:01 PM, Fred Massey wrote:
>>> Good afternoon,
>>>
>>> I have successfully connected my QSR-1 to my K3s if-out, and immediately
>>> noticed the signal strengths showing on the QSR-1 were much weaker. I
>>> probably have an early K3s, so the if-out signal strength is even weaker.
>>>
>>> Any recommendations at a good preamp to use? It seems like 20db is what
>> I
>>> need:
>>>
>>> 73,
>>> Fred
>>> AE4ED
>>
>> ______________________________________________________________
>> Elecraft mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:[hidden email]
>>
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html
>> Message delivered to [hidden email]
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> Message delivered to [hidden email]
>

AE4ED

Re: preamp for using an SDR as a pan adapter

Some. I was planning on sending an email to Elecraft support with the s/n
of my K3s to see if I needed the mod. The difference I’m seeing in signal
strength is about 20+ dB. Is it normal for the if-out to be weaker than a
direct connection to the antenna?
73,
Fred
AE4ED

On Fri, Oct 4, 2019 at 12:44 PM Don Wilhelm <[hidden email]> wrote:

> Fred,
>
> Have you looked the K3 IF Output mod?
>
> https://ftp.elecraft.com/K3/Mod%20Notes%20Alerts/IF_Output_Buffer_Gain_Mod_Rev_A.pdf
>
> If you don't have the 13k SMD resistor or a 1/8 watt 13k resistor, you
> can order the kit from Elecraft.
>
> 73,
> Don W3FPR
>
> On 10/4/2019 1:24 PM, Fred Massey wrote:
> > Good afternoon Wes and all,
> >
> > If I connect the antenna directly to the QSR-1, I get the same signal
> level
> > as the K3s. But, when I connect to the QSR-1 to the IF-out, the signal
> is
> > about 4 s-units less.
> >
> > Any ideas...anyone?
> >
> > Fred
> >
> > On Thu, Oct 3, 2019 at 4:14 PM Wes <[hidden email]> wrote:
> >
> >> I use an SDR-IQ on the i-f output on my (very) early K3S. it works
> fine.
> >> IIRC,
> >> always a dubious proposition, I did the mod on my original K3 and it
> >> worked well
> >> too without any additional amplification. I think you have another
> >> problem.
> >>
> >> Wes N7WS
> >>
> >> On 10/3/2019 2:01 PM, Fred Massey wrote:
> >>> Good afternoon,
> >>>
> >>> I have successfully connected my QSR-1 to my K3s if-out, and
> immediately
> >>> noticed the signal strengths showing on the QSR-1 were much weaker. I
> >>> probably have an early K3s, so the if-out signal strength is even
> weaker.
> >>>
> >>> Any recommendations at a good preamp to use? It seems like 20db is
> what
> >> I
> >>> need:
> >>>
> >>> 73,
> >>> Fred
> >>> AE4ED
> >>
> >> ______________________________________________________________
> >> Elecraft mailing list
> >> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> >> Help: http://mailman.qth.net/mmfaq.htm
> >> Post: mailto:[hidden email]
> >>
> >> This list hosted by: http://www.qsl.net
> >> Please help support this email list: http://www.qsl.net/donate.html
> >> Message delivered to [hidden email]
> > ______________________________________________________________
> > Elecraft mailing list
> > Home: http://mailman.qth.net/mailman/listinfo/elecraft
> > Help: http://mailman.qth.net/mmfaq.htm
> > Post: mailto:[hidden email]
> >
> > This list hosted by: http://www.qsl.net
> > Please help support this email list: http://www.qsl.net/donate.html
> > Message delivered to [hidden email]
> >
>

Wes Stewart-2

Re: preamp for using an SDR as a pan adapter

In reply to this post by Don Wilhelm

He says he has a K3S. They don't need the mod.

On 10/4/2019 10:43 AM, Don Wilhelm wrote:

> Fred,
>
> Have you looked the K3 IF Output mod?
> https://ftp.elecraft.com/K3/Mod%20Notes%20Alerts/IF_Output_Buffer_Gain_Mod_Rev_A.pdf
>
> If you don't have the 13k SMD resistor or a 1/8 watt 13k resistor, you can
> order the kit from Elecraft.
>
> 73,
> Don W3FPR
>
> On 10/4/2019 1:24 PM, Fred Massey wrote:
>> Good afternoon Wes and all,
>>
>> If I connect the antenna directly to the QSR-1, I get the same signal level
>> as the K3s. But, when I connect to the QSR-1 to the IF-out, the signal is
>> about 4 s-units less.
>>
>> Any ideas...anyone?
>>
>> Fred
>>
>> O

Wes Stewart-2

Re: preamp for using an SDR as a pan adapter

In reply to this post by AE4ED

I just ran a test on my K3S configuration. Using an XG-2 on 20 meters and the
SDR-IQ, which is very well calibrated, the i-f output is 6 dB below the antenna
input.

Wes N7WS

On 10/4/2019 10:57 AM, Fred Massey wrote:
> Some. I was planning on sending an email to Elecraft support with the s/n of
> my K3s to see if I needed the mod. The difference I’m seeing in signal
> strength is about 20+ dB. Is it normal for the if-out to be weaker than a
> direct connection to the antenna?
> 73,
> Fred
> AE4ED

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Post: mailto:[hidden email]

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Bob McGraw - K4TAX

Re: preamp for using an SDR as a pan adapter

In reply to this post by AE4ED

In a word, YES. I find that to be true with my K3S as well as other
brands/models of radios. Thus you'll need about 20 dB of gain in the
form of a preamp between the IF output and the QSR receiver.

73

Bob, K4TAX

On 10/4/2019 12:57 PM, Fred Massey wrote:

> Some. I was planning on sending an email to Elecraft support with the s/n
> of my K3s to see if I needed the mod. The difference I’m seeing in signal
> strength is about 20+ dB. Is it normal for the if-out to be weaker than a
> direct connection to the antenna?
> 73,
> Fred
> AE4ED
>
> On Fri, Oct 4, 2019 at 12:44 PM Don Wilhelm <[hidden email]> wrote:
>
>> Fred,
>>
>> Have you looked the K3 IF Output mod?
>>
>> https://ftp.elecraft.com/K3/Mod%20Notes%20Alerts/IF_Output_Buffer_Gain_Mod_Rev_A.pdf
>>
>> If you don't have the 13k SMD resistor or a 1/8 watt 13k resistor, you
>> can order the kit from Elecraft.
>>
>> 73,
>> Don W3FPR
>>
>> On 10/4/2019 1:24 PM, Fred Massey wrote:
>>> Good afternoon Wes and all,
>>>
>>> If I connect the antenna directly to the QSR-1, I get the same signal
>> level
>>> as the K3s. But, when I connect to the QSR-1 to the IF-out, the signal
>> is
>>> about 4 s-units less.
>>>
>>> Any ideas...anyone?
>>>
>>> Fred
>>>
>>> On Thu, Oct 3, 2019 at 4:14 PM Wes <[hidden email]> wrote:
>>>
>>>> I use an SDR-IQ on the i-f output on my (very) early K3S. it works
>> fine.
>>>> IIRC,
>>>> always a dubious proposition, I did the mod on my original K3 and it
>>>> worked well
>>>> too without any additional amplification. I think you have another
>>>> problem.
>>>>
>>>> Wes N7WS
>>>>
>>>> On 10/3/2019 2:01 PM, Fred Massey wrote:
>>>>> Good afternoon,
>>>>>
>>>>> I have successfully connected my QSR-1 to my K3s if-out, and
>> immediately
>>>>> noticed the signal strengths showing on the QSR-1 were much weaker. I
>>>>> probably have an early K3s, so the if-out signal strength is even
>> weaker.
>>>>> Any recommendations at a good preamp to use? It seems like 20db is
>> what
>>>> I
>>>>> need:
>>>>>
>>>>> 73,
>>>>> Fred
>>>>> AE4ED
>>>> ______________________________________________________________
>>>> Elecraft mailing list
>>>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>>>> Help: http://mailman.qth.net/mmfaq.htm
>>>> Post: mailto:[hidden email]
>>>>
>>>> This list hosted by: http://www.qsl.net
>>>> Please help support this email list: http://www.qsl.net/donate.html
>>>> Message delivered to [hidden email]
>>> ______________________________________________________________
>>> Elecraft mailing list
>>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>>> Help: http://mailman.qth.net/mmfaq.htm
>>> Post: mailto:[hidden email]
>>>
>>> This list hosted by: http://www.qsl.net
>>> Please help support this email list: http://www.qsl.net/donate.html
>>> Message delivered to [hidden email]
>>>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> Message delivered to [hidden email]

AE4ED

Re: preamp for using an SDR as a pan adapter

In reply to this post by Wes Stewart-2

I read that early K3s also needed the mod.

Wes, thanks your measurements make sense, and I suspect that is normal.

Fred

On Fri, Oct 4, 2019 at 2:15 PM Wes <[hidden email]> wrote:

> I just ran a test on my K3S configuration. Using an XG-2 on 20 meters and
> the
> SDR-IQ, which is very well calibrated, the i-f output is 6 dB below the
> antenna
> input.
>
> Wes N7WS
>
> On 10/4/2019 10:57 AM, Fred Massey wrote:
> > Some. I was planning on sending an email to Elecraft support with the
> s/n of
> > my K3s to see if I needed the mod. The difference I’m seeing in signal
> > strength is about 20+ dB. Is it normal for the if-out to be weaker than
> a
> > direct connection to the antenna?
> > 73,
> > Fred
> > AE4ED
>
>

AE4ED

Re: preamp for using an SDR as a pan adapter

In reply to this post by Bob McGraw - K4TAX

A friend of mine, Tim AB4B, suggested that I might need a buffer amp to
keep the IF being pulled down by the sdr. DXEngineering sells the Clifton
Z10000. That adds about 6db of gain, but maybe the buffering that it does
has an even bigger effect.

On Fri, Oct 4, 2019 at 2:18 PM Bob McGraw K4TAX <[hidden email]> wrote:

> In a word, YES. I find that to be true with my K3S as well as other
> brands/models of radios. Thus you'll need about 20 dB of gain in the
> form of a preamp between the IF output and the QSR receiver.
>
> 73
>
> Bob, K4TAX
>
>
> On 10/4/2019 12:57 PM, Fred Massey wrote:
> > Some. I was planning on sending an email to Elecraft support with the
> s/n
> > of my K3s to see if I needed the mod. The difference I’m seeing in
> signal
> > strength is about 20+ dB. Is it normal for the if-out to be weaker than
> a
> > direct connection to the antenna?
> > 73,
> > Fred
> > AE4ED
> >
> > On Fri, Oct 4, 2019 at 12:44 PM Don Wilhelm <[hidden email]>
> wrote:
> >
> >> Fred,
> >>
> >> Have you looked the K3 IF Output mod?
> >>
> >>
> https://ftp.elecraft.com/K3/Mod%20Notes%20Alerts/IF_Output_Buffer_Gain_Mod_Rev_A.pdf
> >>
> >> If you don't have the 13k SMD resistor or a 1/8 watt 13k resistor, you
> >> can order the kit from Elecraft.
> >>
> >> 73,
> >> Don W3FPR
> >>
> >> On 10/4/2019 1:24 PM, Fred Massey wrote:
> >>> Good afternoon Wes and all,
> >>>
> >>> If I connect the antenna directly to the QSR-1, I get the same signal
> >> level
> >>> as the K3s. But, when I connect to the QSR-1 to the IF-out, the signal
> >> is
> >>> about 4 s-units less.
> >>>
> >>> Any ideas...anyone?
> >>>
> >>> Fred
> >>>
> >>> On Thu, Oct 3, 2019 at 4:14 PM Wes <[hidden email]> wrote:
> >>>
> >>>> I use an SDR-IQ on the i-f output on my (very) early K3S. it works
> >> fine.
> >>>> IIRC,
> >>>> always a dubious proposition, I did the mod on my original K3 and it
> >>>> worked well
> >>>> too without any additional amplification. I think you have another
> >>>> problem.
> >>>>
> >>>> Wes N7WS
> >>>>
> >>>> On 10/3/2019 2:01 PM, Fred Massey wrote:
> >>>>> Good afternoon,
> >>>>>
> >>>>> I have successfully connected my QSR-1 to my K3s if-out, and
> >> immediately
> >>>>> noticed the signal strengths showing on the QSR-1 were much weaker.
> I
> >>>>> probably have an early K3s, so the if-out signal strength is even
> >> weaker.
> >>>>> Any recommendations at a good preamp to use? It seems like 20db is
> >> what
> >>>> I
> >>>>> need:
> >>>>>
> >>>>> 73,
> >>>>> Fred
> >>>>> AE4ED
> >>>> ______________________________________________________________
> >>>> Elecraft mailing list
> >>>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> >>>> Help: http://mailman.qth.net/mmfaq.htm
> >>>> Post: mailto:[hidden email]
> >>>>
> >>>> This list hosted by: http://www.qsl.net
> >>>> Please help support this email list: http://www.qsl.net/donate.html
> >>>> Message delivered to [hidden email]
> >>> ______________________________________________________________
> >>> Elecraft mailing list
> >>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> >>> Help: http://mailman.qth.net/mmfaq.htm
> >>> Post: mailto:[hidden email]
> >>>
> >>> This list hosted by: http://www.qsl.net
> >>> Please help support this email list: http://www.qsl.net/donate.html
> >>> Message delivered to [hidden email]
> >>>
> > ______________________________________________________________
> > Elecraft mailing list
> > Home: http://mailman.qth.net/mailman/listinfo/elecraft
> > Help: http://mailman.qth.net/mmfaq.htm
> > Post: mailto:[hidden email]
> >
> > This list hosted by: http://www.qsl.net
> > Please help support this email list: http://www.qsl.net/donate.html
> > Message delivered to [hidden email]
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> Message delivered to [hidden email]

Bob McGraw - K4TAX

Re: preamp for using an SDR as a pan adapter

I read that folks have successfully used the Clifton buffer amp.
Certainly worth a try.   Others have indicated only about 6 dB of gain
is needed.

The software I use for my RSP-1 allows RF Gain changes. Thus with the
lower IF output of my K3S, I just raise the gain of the RSP-1 via the
software. I've never considered the SDR receivers of that type to be
very precise with regard to "calibration". Although some seem to think
they can split hairs on a mosquito with the level and frequency accuracy
of the receivers.    I do not consider them of instrumentation quality,
thus anything +/-10 dB is deemed satisfactory. Likewise the same with
frequency accuracy. Others may have different experiences with
different receivers.

73

Bob, K4TAX

On 10/4/2019 6:34 PM, Fred Massey wrote:

> A friend of mine, Tim AB4B, suggested that I might need a buffer amp
> to keep the IF being pulled down by the sdr. DXEngineering sells the
> Clifton Z10000. That adds about 6db of gain, but maybe the buffering
> that it does has an even bigger effect.
>
> On Fri, Oct 4, 2019 at 2:18 PM Bob McGraw K4TAX <[hidden email]
> <mailto:[hidden email]>> wrote:
>
> In a word, YES. I find that to be true with my K3S as well as other
> brands/models of radios. Thus you'll need about 20 dB of gain in
> the
> form of a preamp between the IF output and the QSR receiver.
>
> 73
>
> Bob, K4TAX
>
>
> On 10/4/2019 12:57 PM, Fred Massey wrote:
> > Some. I was planning on sending an email to Elecraft support
> with the s/n
> > of my K3s to see if I needed the mod. The difference I’m seeing
> in signal
> > strength is about 20+ dB. Is it normal for the if-out to be
> weaker than a
> > direct connection to the antenna?
> > 73,
> > Fred
> > AE4ED
> >
> > On Fri, Oct 4, 2019 at 12:44 PM Don Wilhelm
> <[hidden email] <mailto:[hidden email]>> wrote:
> >
> >> Fred,
> >>
> >> Have you looked the K3 IF Output mod?
> >>
> >>
> https://ftp.elecraft.com/K3/Mod%20Notes%20Alerts/IF_Output_Buffer_Gain_Mod_Rev_A.pdf
> >>
> >> If you don't have the 13k SMD resistor or a 1/8 watt 13k
> resistor, you
> >> can order the kit from Elecraft.
> >>
> >> 73,
> >> Don W3FPR
> >>
> >> On 10/4/2019 1:24 PM, Fred Massey wrote:
> >>> Good afternoon Wes and all,
> >>>
> >>> If I connect the antenna directly to the QSR-1, I get the same
> signal
> >> level
> >>> as the K3s. But, when I connect to the QSR-1 to the IF-out,
> the signal
> >> is
> >>> about 4 s-units less.
> >>>
> >>> Any ideas...anyone?
> >>>
> >>> Fred
> >>>
> >>> On Thu, Oct 3, 2019 at 4:14 PM Wes <[hidden email]
> <mailto:[hidden email]>> wrote:
> >>>
> >>>> I use an SDR-IQ on the i-f output on my (very) early K3S. it
> works
> >> fine.
> >>>> IIRC,
> >>>> always a dubious proposition, I did the mod on my original K3
> and it
> >>>> worked well
> >>>> too without any additional amplification. I think you have
> another
> >>>> problem.
> >>>>
> >>>> Wes N7WS
> >>>>
> >>>> On 10/3/2019 2:01 PM, Fred Massey wrote:
> >>>>> Good afternoon,
> >>>>>
> >>>>> I have successfully connected my QSR-1 to my K3s if-out, and
> >> immediately
> >>>>> noticed the signal strengths showing on the QSR-1 were much
> weaker. I
> >>>>> probably have an early K3s, so the if-out signal strength is
> even
> >> weaker.
> >>>>> Any recommendations at a good preamp to use? It seems like
> 20db is
> >> what
> >>>> I
> >>>>> need:
> >>>>>
> >>>>> 73,
> >>>>> Fred
> >>>>> AE4ED
> >>>> ______________________________________________________________
> >>>> Elecraft mailing list
> >>>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> >>>> Help: http://mailman.qth.net/mmfaq.htm
> >>>> Post: mailto:[hidden email]
> <mailto:[hidden email]>
> >>>>
> >>>> This list hosted by: http://www.qsl.net
> >>>> Please help support this email list:
> http://www.qsl.net/donate.html
> >>>> Message delivered to [hidden email]
> <mailto:[hidden email]>
> >>> ______________________________________________________________
> >>> Elecraft mailing list
> >>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> >>> Help: http://mailman.qth.net/mmfaq.htm
> >>> Post: mailto:[hidden email]
> <mailto:[hidden email]>
> >>>
> >>> This list hosted by: http://www.qsl.net
> >>> Please help support this email list:
> http://www.qsl.net/donate.html
> >>> Message delivered to [hidden email]
> <mailto:[hidden email]>
> >>>
> > ______________________________________________________________
> > Elecraft mailing list
> > Home: http://mailman.qth.net/mailman/listinfo/elecraft
> > Help: http://mailman.qth.net/mmfaq.htm
> > Post: mailto:[hidden email]
> <mailto:[hidden email]>
> >
> > This list hosted by: http://www.qsl.net
> > Please help support this email list: http://www.qsl.net/donate.html
> > Message delivered to [hidden email]
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AE4ED

Re: preamp for using an SDR as a pan adapter

I knew I had an issue when I could hear signals on the K3s that weren’t
showing on the waterfall.

I need to engage Elecraft tech support to see if I need the mod for my K3s,
and see what they say about using an external buffer amp or preamp.

When I posted, I thought this might be a common problem that others had
fixed before.

On Fri, Oct 4, 2019 at 6:59 PM Bob McGraw K4TAX <[hidden email]> wrote:

> I read that folks have successfully used the Clifton buffer amp.
> Certainly worth a try. Others have indicated only about 6 dB of gain is
> needed.
>
> The software I use for my RSP-1 allows RF Gain changes. Thus with the
> lower IF output of my K3S, I just raise the gain of the RSP-1 via the
> software. I've never considered the SDR receivers of that type to be very
> precise with regard to "calibration". Although some seem to think they
> can split hairs on a mosquito with the level and frequency accuracy of the
> receivers. I do not consider them of instrumentation quality, thus
> anything +/-10 dB is deemed satisfactory. Likewise the same with frequency
> accuracy. Others may have different experiences with different receivers.
>
> 73
>
> Bob, K4TAX
>
>
> On 10/4/2019 6:34 PM, Fred Massey wrote:
>
> A friend of mine, Tim AB4B, suggested that I might need a buffer amp to
> keep the IF being pulled down by the sdr. DXEngineering sells the Clifton
> Z10000. That adds about 6db of gain, but maybe the buffering that it does
> has an even bigger effect.
>
> On Fri, Oct 4, 2019 at 2:18 PM Bob McGraw K4TAX <[hidden email]>
> wrote:
>
>> In a word, YES. I find that to be true with my K3S as well as other
>> brands/models of radios. Thus you'll need about 20 dB of gain in the
>> form of a preamp between the IF output and the QSR receiver.
>>
>> 73
>>
>> Bob, K4TAX
>>
>>
>> On 10/4/2019 12:57 PM, Fred Massey wrote:
>> > Some. I was planning on sending an email to Elecraft support with the
>> s/n
>> > of my K3s to see if I needed the mod. The difference I’m seeing in
>> signal
>> > strength is about 20+ dB. Is it normal for the if-out to be weaker
>> than a
>> > direct connection to the antenna?
>> > 73,
>> > Fred
>> > AE4ED
>> >
>> > On Fri, Oct 4, 2019 at 12:44 PM Don Wilhelm <[hidden email]>
>> wrote:
>> >
>> >> Fred,
>> >>
>> >> Have you looked the K3 IF Output mod?
>> >>
>> >>
>> https://ftp.elecraft.com/K3/Mod%20Notes%20Alerts/IF_Output_Buffer_Gain_Mod_Rev_A.pdf
>> >>
>> >> If you don't have the 13k SMD resistor or a 1/8 watt 13k resistor, you
>> >> can order the kit from Elecraft.
>> >>
>> >> 73,
>> >> Don W3FPR
>> >>
>> >> On 10/4/2019 1:24 PM, Fred Massey wrote:
>> >>> Good afternoon Wes and all,
>> >>>
>> >>> If I connect the antenna directly to the QSR-1, I get the same signal
>> >> level
>> >>> as the K3s. But, when I connect to the QSR-1 to the IF-out, the
>> signal
>> >> is
>> >>> about 4 s-units less.
>> >>>
>> >>> Any ideas...anyone?
>> >>>
>> >>> Fred
>> >>>
>> >>> On Thu, Oct 3, 2019 at 4:14 PM Wes <[hidden email]> wrote:
>> >>>
>> >>>> I use an SDR-IQ on the i-f output on my (very) early K3S. it works
>> >> fine.
>> >>>> IIRC,
>> >>>> always a dubious proposition, I did the mod on my original K3 and it
>> >>>> worked well
>> >>>> too without any additional amplification. I think you have another
>> >>>> problem.
>> >>>>
>> >>>> Wes N7WS
>> >>>>
>> >>>> On 10/3/2019 2:01 PM, Fred Massey wrote:
>> >>>>> Good afternoon,
>> >>>>>
>> >>>>> I have successfully connected my QSR-1 to my K3s if-out, and
>> >> immediately
>> >>>>> noticed the signal strengths showing on the QSR-1 were much
>> weaker. I
>> >>>>> probably have an early K3s, so the if-out signal strength is even
>> >> weaker.
>> >>>>> Any recommendations at a good preamp to use? It seems like 20db is
>> >> what
>> >>>> I
>> >>>>> need:
>> >>>>>
>> >>>>> 73,
>> >>>>> Fred
>> >>>>> AE4ED
>> >>>> ______________________________________________________________
>> >>>> Elecraft mailing list
>> >>>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>> >>>> Help: http://mailman.qth.net/mmfaq.htm
>> >>>> Post: mailto:[hidden email]
>> >>>>
>> >>>> This list hosted by: http://www.qsl.net
>> >>>> Please help support this email list: http://www.qsl.net/donate.html
>> >>>> Message delivered to [hidden email]
>> >>> ______________________________________________________________
>> >>> Elecraft mailing list
>> >>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>> >>> Help: http://mailman.qth.net/mmfaq.htm
>> >>> Post: mailto:[hidden email]
>> >>>
>> >>> This list hosted by: http://www.qsl.net
>> >>> Please help support this email list: http://www.qsl.net/donate.html
>> >>> Message delivered to [hidden email]
>> >>>
>> > ______________________________________________________________
>> > Elecraft mailing list
>> > Home: http://mailman.qth.net/mailman/listinfo/elecraft
>> > Help: http://mailman.qth.net/mmfaq.htm
>> > Post: mailto:[hidden email]
>> >
>> > This list hosted by: http://www.qsl.net
>> > Please help support this email list: http://www.qsl.net/donate.html
>> > Message delivered to [hidden email]
>>
>> ______________________________________________________________
>> Elecraft mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:[hidden email]
>>
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html
>> Message delivered to [hidden email]
>
>

Don Wilhelm

Re: preamp for using an SDR as a pan adapter

Fred,

Is that "K3S" or multiple "K3"s?
All The K3S have the mod, as well as later K3s. If an early K3, then
you may need the mod.

73,
Don W3FPR

On 10/4/2019 8:59 PM, Fred Massey wrote:

> I knew I had an issue when I could hear signals on the K3s that weren’t
> showing on the waterfall.
>
> I need to engage Elecraft tech support to see if I need the mod for my K3s,
> and see what they say about using an external buffer amp or preamp.
>
> When I posted, I thought this might be a common problem that others had
> fixed before.
>
>
> On Fri, Oct 4, 2019 at 6:59 PM Bob McGraw K4TAX <[hidden email]> wrote:
>
>> I read that folks have successfully used the Clifton buffer amp.
>> Certainly worth a try. Others have indicated only about 6 dB of gain is
>> needed.
>>
>> The software I use for my RSP-1 allows RF Gain changes. Thus with the
>> lower IF output of my K3S, I just raise the gain of the RSP-1 via the
>> software. I've never considered the SDR receivers of that type to be very
>> precise with regard to "calibration". Although some seem to think they
>> can split hairs on a mosquito with the level and frequency accuracy of the
>> receivers. I do not consider them of instrumentation quality, thus
>> anything +/-10 dB is deemed satisfactory. Likewise the same with frequency
>> accuracy. Others may have different experiences with different receivers.
>>
>> 73
>>
>> Bob, K4TAX
>>
>>
>> On 10/4/2019 6:34 PM, Fred Massey wrote:
>>
>> A friend of mine, Tim AB4B, suggested that I might need a buffer amp to
>> keep the IF being pulled down by the sdr. DXEngineering sells the Clifton
>> Z10000. That adds about 6db of gain, but maybe the buffering that it does
>> has an even bigger effect.
>>
>> On Fri, Oct 4, 2019 at 2:18 PM Bob McGraw K4TAX <[hidden email]>
>> wrote:
>>
>>> In a word, YES. I find that to be true with my K3S as well as other
>>> brands/models of radios. Thus you'll need about 20 dB of gain in the
>>> form of a preamp between the IF output and the QSR receiver.
>>>
>>> 73
>>>
>>> Bob, K4TAX
>>>
>>>
>>> On 10/4/2019 12:57 PM, Fred Massey wrote:
>>>> Some. I was planning on sending an email to Elecraft support with the
>>> s/n
>>>> of my K3s to see if I needed the mod. The difference I’m seeing in
>>> signal
>>>> strength is about 20+ dB. Is it normal for the if-out to be weaker
>>> than a
>>>> direct connection to the antenna?
>>>> 73,
>>>> Fred
>>>> AE4ED
>>>>
>>>> On Fri, Oct 4, 2019 at 12:44 PM Don Wilhelm <[hidden email]>
>>> wrote:
>>>>
>>>>> Fred,
>>>>>
>>>>> Have you looked the K3 IF Output mod?
>>>>>
>>>>>
>>> https://ftp.elecraft.com/K3/Mod%20Notes%20Alerts/IF_Output_Buffer_Gain_Mod_Rev_A.pdf
>>>>>
>>>>> If you don't have the 13k SMD resistor or a 1/8 watt 13k resistor, you
>>>>> can order the kit from Elecraft.
>>>>>
>>>>> 73,
>>>>> Don W3FPR
>>>>>
>>>>> On 10/4/2019 1:24 PM, Fred Massey wrote:
>>>>>> Good afternoon Wes and all,
>>>>>>
>>>>>> If I connect the antenna directly to the QSR-1, I get the same signal
>>>>> level
>>>>>> as the K3s. But, when I connect to the QSR-1 to the IF-out, the
>>> signal
>>>>> is
>>>>>> about 4 s-units less.
>>>>>>
>>>>>> Any ideas...anyone?
>>>>>>
>>>>>> Fred
>>>>>>
>>>>>> On Thu, Oct 3, 2019 at 4:14 PM Wes <[hidden email]> wrote:
>>>>>>
>>>>>>> I use an SDR-IQ on the i-f output on my (very) early K3S. it works
>>>>> fine.
>>>>>>> IIRC,
>>>>>>> always a dubious proposition, I did the mod on my original K3 and it
>>>>>>> worked well
>>>>>>> too without any additional amplification. I think you have another
>>>>>>> problem.
>>>>>>>
>>>>>>> Wes N7WS
>>>>>>>
>>>>>>> On 10/3/2019 2:01 PM, Fred Massey wrote:
>>>>>>>> Good afternoon,
>>>>>>>>
>>>>>>>> I have successfully connected my QSR-1 to my K3s if-out, and
>>>>> immediately
>>>>>>>> noticed the signal strengths showing on the QSR-1 were much
>>> weaker. I
>>>>>>>> probably have an early K3s, so the if-out signal strength is even
>>>>> weaker.
>>>>>>>> Any recommendations at a good preamp to use? It seems like 20db is
>>>>> what
>>>>>>> I
>>>>>>>> need:
>>>>>>>>
>>>>>>>> 73,
>>>>>>>> Fred
>>>>>>>> AE4ED
>>>>>>> ______________________________________________________________
>>>>>>> Elecraft mailing list
>>>>>>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>>>>>>> Help: http://mailman.qth.net/mmfaq.htm
>>>>>>> Post: mailto:[hidden email]
>>>>>>>
>>>>>>> This list hosted by: http://www.qsl.net
>>>>>>> Please help support this email list: http://www.qsl.net/donate.html
>>>>>>> Message delivered to [hidden email]
>>>>>> ______________________________________________________________
>>>>>> Elecraft mailing list
>>>>>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>>>>>> Help: http://mailman.qth.net/mmfaq.htm
>>>>>> Post: mailto:[hidden email]
>>>>>>
>>>>>> This list hosted by: http://www.qsl.net
>>>>>> Please help support this email list: http://www.qsl.net/donate.html
>>>>>> Message delivered to [hidden email]
>>>>>>
>>>> ______________________________________________________________
>>>> Elecraft mailing list
>>>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>>>> Help: http://mailman.qth.net/mmfaq.htm
>>>> Post: mailto:[hidden email]
>>>>
>>>> This list hosted by: http://www.qsl.net
>>>> Please help support this email list: http://www.qsl.net/donate.html
>>>> Message delivered to [hidden email]
>>>
>>> ______________________________________________________________
>>> Elecraft mailing list
>>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>>> Help: http://mailman.qth.net/mmfaq.htm
>>> Post: mailto:[hidden email]
>>>
>>> This list hosted by: http://www.qsl.net
>>> Please help support this email list: http://www.qsl.net/donate.html
>>> Message delivered to [hidden email]
>>
>>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> Message delivered to [hidden email]
>

AE4ED

Re: preamp for using an SDR as a pan adapter

It a K3S. I’m about to order Clifton Labs Z10000C kit from DX
Engineering. Any better ideas are welcome:

On Fri, Oct 4, 2019 at 8:27 PM Don Wilhelm <[hidden email]> wrote:

> Fred,
>
> Is that "K3S" or multiple "K3"s?
> All The K3S have the mod, as well as later K3s. If an early K3, then
> you may need the mod.
>
> 73,
> Don W3FPR
>
> On 10/4/2019 8:59 PM, Fred Massey wrote:
> > I knew I had an issue when I could hear signals on the K3s that weren’t
> > showing on the waterfall.
> >
> > I need to engage Elecraft tech support to see if I need the mod for my
> K3s,
> > and see what they say about using an external buffer amp or preamp.
> >
> > When I posted, I thought this might be a common problem that others had
> > fixed before.
> >
> >
> > On Fri, Oct 4, 2019 at 6:59 PM Bob McGraw K4TAX <[hidden email]>
> wrote:
> >
> >> I read that folks have successfully used the Clifton buffer amp.
> >> Certainly worth a try. Others have indicated only about 6 dB of gain
> is
> >> needed.
> >>
> >> The software I use for my RSP-1 allows RF Gain changes. Thus with the
> >> lower IF output of my K3S, I just raise the gain of the RSP-1 via the
> >> software. I've never considered the SDR receivers of that type to be
> very
> >> precise with regard to "calibration". Although some seem to think
> they
> >> can split hairs on a mosquito with the level and frequency accuracy of
> the
> >> receivers. I do not consider them of instrumentation quality, thus
> >> anything +/-10 dB is deemed satisfactory. Likewise the same with
> frequency
> >> accuracy. Others may have different experiences with different
> receivers.
> >>
> >> 73
> >>
> >> Bob, K4TAX
> >>
> >>
> >> On 10/4/2019 6:34 PM, Fred Massey wrote:
> >>
> >> A friend of mine, Tim AB4B, suggested that I might need a buffer amp to
> >> keep the IF being pulled down by the sdr. DXEngineering sells the
> Clifton
> >> Z10000. That adds about 6db of gain, but maybe the buffering that it
> does
> >> has an even bigger effect.
> >>
> >> On Fri, Oct 4, 2019 at 2:18 PM Bob McGraw K4TAX <[hidden email]>
> >> wrote:
> >>
> >>> In a word, YES. I find that to be true with my K3S as well as other
> >>> brands/models of radios. Thus you'll need about 20 dB of gain in the
> >>> form of a preamp between the IF output and the QSR receiver.
> >>>
> >>> 73
> >>>
> >>> Bob, K4TAX
> >>>
> >>>
> >>> On 10/4/2019 12:57 PM, Fred Massey wrote:
> >>>> Some. I was planning on sending an email to Elecraft support with the
> >>> s/n
> >>>> of my K3s to see if I needed the mod. The difference I’m seeing in
> >>> signal
> >>>> strength is about 20+ dB. Is it normal for the if-out to be weaker
> >>> than a
> >>>> direct connection to the antenna?
> >>>> 73,
> >>>> Fred
> >>>> AE4ED
> >>>>
> >>>> On Fri, Oct 4, 2019 at 12:44 PM Don Wilhelm <[hidden email]>
> >>> wrote:
> >>>>
> >>>>> Fred,
> >>>>>
> >>>>> Have you looked the K3 IF Output mod?
> >>>>>
> >>>>>
> >>>
> https://ftp.elecraft.com/K3/Mod%20Notes%20Alerts/IF_Output_Buffer_Gain_Mod_Rev_A.pdf
> >>>>>
> >>>>> If you don't have the 13k SMD resistor or a 1/8 watt 13k resistor,
> you
> >>>>> can order the kit from Elecraft.
> >>>>>
> >>>>> 73,
> >>>>> Don W3FPR
> >>>>>
> >>>>> On 10/4/2019 1:24 PM, Fred Massey wrote:
> >>>>>> Good afternoon Wes and all,
> >>>>>>
> >>>>>> If I connect the antenna directly to the QSR-1, I get the same
> signal
> >>>>> level
> >>>>>> as the K3s. But, when I connect to the QSR-1 to the IF-out, the
> >>> signal
> >>>>> is
> >>>>>> about 4 s-units less.
> >>>>>>
> >>>>>> Any ideas...anyone?
> >>>>>>
> >>>>>> Fred
> >>>>>>
> >>>>>> On Thu, Oct 3, 2019 at 4:14 PM Wes <[hidden email]> wrote:
> >>>>>>
> >>>>>>> I use an SDR-IQ on the i-f output on my (very) early K3S. it works
> >>>>> fine.
> >>>>>>> IIRC,
> >>>>>>> always a dubious proposition, I did the mod on my original K3 and
> it
> >>>>>>> worked well
> >>>>>>> too without any additional amplification. I think you have another
> >>>>>>> problem.
> >>>>>>>
> >>>>>>> Wes N7WS
> >>>>>>>
> >>>>>>> On 10/3/2019 2:01 PM, Fred Massey wrote:
> >>>>>>>> Good afternoon,
> >>>>>>>>
> >>>>>>>> I have successfully connected my QSR-1 to my K3s if-out, and
> >>>>> immediately
> >>>>>>>> noticed the signal strengths showing on the QSR-1 were much
> >>> weaker. I
> >>>>>>>> probably have an early K3s, so the if-out signal strength is even
> >>>>> weaker.
> >>>>>>>> Any recommendations at a good preamp to use? It seems like 20db
> is
> >>>>> what
> >>>>>>> I
> >>>>>>>> need:
> >>>>>>>>
> >>>>>>>> 73,
> >>>>>>>> Fred
> >>>>>>>> AE4ED
> >>>>>>> ______________________________________________________________
> >>>>>>> Elecraft mailing list
> >>>>>>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> >>>>>>> Help: http://mailman.qth.net/mmfaq.htm
> >>>>>>> Post: mailto:[hidden email]
> >>>>>>>
> >>>>>>> This list hosted by: http://www.qsl.net
> >>>>>>> Please help support this email list:
> http://www.qsl.net/donate.html
> >>>>>>> Message delivered to [hidden email]
> >>>>>> ______________________________________________________________
> >>>>>> Elecraft mailing list
> >>>>>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> >>>>>> Help: http://mailman.qth.net/mmfaq.htm
> >>>>>> Post: mailto:[hidden email]
> >>>>>>
> >>>>>> This list hosted by: http://www.qsl.net
> >>>>>> Please help support this email list: http://www.qsl.net/donate.html
> >>>>>> Message delivered to [hidden email]
> >>>>>>
> >>>> ______________________________________________________________
> >>>> Elecraft mailing list
> >>>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> >>>> Help: http://mailman.qth.net/mmfaq.htm
> >>>> Post: mailto:[hidden email]
> >>>>
> >>>> This list hosted by: http://www.qsl.net
> >>>> Please help support this email list: http://www.qsl.net/donate.html
> >>>> Message delivered to [hidden email]
> >>>
> >>> ______________________________________________________________
> >>> Elecraft mailing list
> >>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> >>> Help: http://mailman.qth.net/mmfaq.htm
> >>> Post: mailto:[hidden email]
> >>>
> >>> This list hosted by: http://www.qsl.net
> >>> Please help support this email list: http://www.qsl.net/donate.html
> >>> Message delivered to [hidden email]
> >>
> >>
> > ______________________________________________________________
> > Elecraft mailing list
> > Home: http://mailman.qth.net/mailman/listinfo/elecraft
> > Help: http://mailman.qth.net/mmfaq.htm
> > Post: mailto:[hidden email]
> >
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> > Please help support this email list: http://www.qsl.net/donate.html
> > Message delivered to [hidden email]
> >
>

Wes Stewart-2

Re: preamp for using an SDR as a pan adapter

In reply to this post by AE4ED

I doubt that the signal is being "pulled down." The source is an FET follower
which should have a low source impedance.

Wes N7WS

On 10/4/2019 4:34 PM, Fred Massey wrote:
> A friend of mine, Tim AB4B, suggested that I might need a buffer amp to
> keep the IF being pulled down by the sdr. DXEngineering sells the Clifton
> Z10000. That adds about 6db of gain, but maybe the buffering that it does
> has an even bigger effect.
>

______________________________________________________________
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Post: mailto:[hidden email]

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Message delivered to [hidden email]

Don Wilhelm

Re: preamp for using an SDR as a pan adapter

I suspect he has a problem with that K3S and should contact support to
see what checks he can make that will be more informative than "It
doesn't work right"

73,
Don W3FPR

On 10/5/2019 1:10 AM, Wes wrote:
> I doubt that the signal is being "pulled down." The source is an FET
> follower which should have a low source impedance.
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