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Digital modes on 144MHz only

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Kjeld Holm

Digital modes on 144MHz only

Digital modes on 144MHz only

I plan for a second station to use for digital modes on 144MHz only. If you look at performance only (no price, no ergonomics, no use outside digital modes on 144MHz) what would you prefer

1) K3/K3S with internal transverter
2) IC-9700

In both cases I plan to use a 1kW amplifier.

Vy 73 de OZ1CCM, Kjeld
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Wes Stewart-2

Re: Digital modes on 144MHz only

I don't know the '9700, but if you already have a K3(S), I would say an external
transverter like an XV144.

Wes N7WS

On 7/4/2019 11:31 AM, Kjeld Holm wrote:

> Digital modes on 144MHz only
>
> I plan for a second station to use for digital modes on 144MHz only. If you look at performance only (no price, no ergonomics, no use outside digital modes on 144MHz) what would you prefer
>
> 1) K3/K3S with internal transverter
> 2) IC-9700
>
> In both cases I plan to use a 1kW amplifier.
>
> Vy 73 de OZ1CCM, Kjeld
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
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>

Bob McGraw - K4TAX

Re: Digital modes on 144MHz only

Make sure you balance the station receive performance with that of the 1
KW amp. Power is easy to generate. Low noise receive performance is
a challenge. Start with a mast mounted low noise preamp, then low loss
feedline such as 7/8" hard-line, and such. Remember, loss in the
feedline adds to receiver noise.

I encounter many stations that have great signals but seemingly can't
hear other stations calling them. I call them alligators.......all
mouth, no ears.

73

Bob, K4TAX

On 7/4/2019 4:14 PM, Wes wrote:

> I don't know the '9700, but if you already have a K3(S), I would say
> an external transverter like an XV144.
>
> Wes N7WS
>
> On 7/4/2019 11:31 AM, Kjeld Holm wrote:
>> Digital modes on 144MHz only
>>
>> I plan for a second station to use for digital modes on 144MHz only.
>> If you look at performance only (no price, no ergonomics, no use
>> outside digital modes on 144MHz) what would you prefer
>>
>> 1) K3/K3S with internal transverter
>> 2) IC-9700
>>
>> In both cases I plan to use a 1kW amplifier.
>>
>> Vy 73 de OZ1CCM, Kjeld
>> ______________________________________________________________
>> Elecraft mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>> Help: http://mailman.qth.net/mmfaq.htm
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>> This list hosted by: http://www.qsl.net
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>
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hbjr

Re: Digital modes on 144MHz only

In reply to this post by Kjeld Holm

I was not happy with the 9700 - it had calibration issues. I returned it.

I have the internal K144XV with the reflock board and 1PPM TXCO installed in
the K3S - the external reference clock for the K3S would be better. So far
it has worked on the few digital modes I have tried. I use an external
soundcard (PK-232sc+) because I like its specs and it also is a real TNC for
packet and pactor. So far so good. I'm only running a 200 watt amplifier.

Hank
K4HYJ

-----Original Message-----
From: [hidden email] <[hidden email]> On
Behalf Of Kjeld Holm
Sent: Thursday, July 4, 2019 2:31 PM
To: Elecraft Reflector <[hidden email]>
Subject: [Elecraft] Digital modes on 144MHz only

Digital modes on 144MHz only

I plan for a second station to use for digital modes on 144MHz only. If you
look at performance only (no price, no ergonomics, no use outside digital
modes on 144MHz) what would you prefer

1) K3/K3S with internal transverter
2) IC-9700

In both cases I plan to use a 1kW amplifier.

Vy 73 de OZ1CCM, Kjeld
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Jim Brown-10

Re: Digital modes on 144MHz only

In reply to this post by Bob McGraw - K4TAX

In today's world, a mast-mounted preamp is a waste of effort for the
vast majority of hams because circuit noise in the receiver is rarely
the limitation on what we hear. Rather it's all the trash from the
electronics in our homes and homes of our neighbors, in addition to
power line noise. I've recently been working 6M grid expeditions to VERY
quiet places, and the ops say that they have to run high power to get
over the local noise of the stations who want to work them. That's why
I bought the KPA1500 that will show up next week. :)

Most of the time, my QTH is pretty quiet, and although I'm running 500W
to 4-el at 120 ft fed with 7/8 hard line, I nearly always give a signal
report that's 10-15dB better than I receive. Today I worked a station
double-hop E-skip who I gave +1 and he gave me -24.

When it's quiet, it's because I worked to make it that way. When it's
not, it's when some new source fires up. One of the things I'd be
concerned about with the internally mounted transverter is frequency
stability due to the additional internally generated heat.

I don't know how they're building them now, but the XV144 and XV220 I
bought used about 15 years ago have serious bonding issues, and they can
be a bit unstable. One of the most serious design faults is the that BNC
I/O connectors are insulated from the shielding enclosure! Hello!
Clearly the designer did the wrong thing to fix whatever instability was
caused by other errors.

73, Jim K9YC

73, Jim K9YC

On 7/4/2019 3:11 PM, Bob McGraw K4TAX wrote:
> Make sure you balance the station receive performance with that of the
> 1 KW amp. Power is easy to generate. Low noise receive performance
> is a challenge. Start with a mast mounted low noise preamp, then low
> loss feedline such as 7/8" hard-line, and such. Remember, loss in the
> feedline adds to receiver noise.
>
> I encounter many stations that have great signals but seemingly can't
> hear other stations calling them. I call them alligators.......all
> mouth, no ears.

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Conrad PA5Y

Re: Digital modes on 144MHz only

In reply to this post by Kjeld Holm

Neither!

I would buy a good transverter to use with a K3S. Two obvious choices.

https://shop.kuhne-electronic.com/kuhne/en/shop/converter-transverte/transverter/TR+144++PRO++Transverter/?card=1621

TR 144 - PRO, Transverter - Kuhne Electronic Amateur Radio Shop<https://shop.kuhne-electronic.com/kuhne/en/shop/converter-transverte/transverter/TR+144++PRO++Transverter/?card=1621>
shop.kuhne-electronic.com
Endkundenshop main_nav Produkte Meta-Description

http://www.ha1ya.hu/htmkepek/me2t_pro3_spec.htm

ME2T-PRO3 & ME2HT-PRO3 transverter specifications<http://www.ha1ya.hu/htmkepek/me2t_pro3_spec.htm>
www.ha1ya.hu
• Frequency Coverage: 144.0-146.0MHz band. • IF in/out Frequency : 28.0-30.0MHz, or 14.0-16.0MHz • LO frq stability: Low phase noise, 1ppm PDI or optional 0.5ppm AXTAL TCXO's! • I/O Impedance : 50 Ohm unbalanced • Input Voltage : 13.8VDC, +-5%, polarity mismatch, 10A -40dB EMI filter. • Power Consumption : 0.55A on RX, 5.5A on TX @30W out version, 10.5A @50W version.
Both of these transverters will outperform the Elecraft transverter with respect to TX PN, IMD and RX IMD. They are both excellent, the HA1YA is considerably cheaper and that is what I chose, actually in my case the ME2T XP because I need 2 channels for Xpol EME. I have extensively tested all these combinations.

The IC9700 is nice and convenient and quite reasonable but both the TX and RX performance is inferior to the K3S with either of the above transverters.

73

Conrad PA5Y

________________________________
From: [hidden email] <[hidden email]> on behalf of Kjeld Holm <[hidden email]>
Sent: 04 July 2019 20:31
To: Elecraft Reflector
Subject: [Elecraft] Digital modes on 144MHz only

Digital modes on 144MHz only

I plan for a second station to use for digital modes on 144MHz only. If you look at performance only (no price, no ergonomics, no use outside digital modes on 144MHz) what would you prefer

1) K3/K3S with internal transverter
2) IC-9700

In both cases I plan to use a 1kW amplifier.

Vy 73 de OZ1CCM, Kjeld
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Michael Walker

Re: Digital modes on 144MHz only

Hi

These are the Transverters I use.

Very good quality and they can be 10mhz gps locked.

http://www.q5signal.com/

Mike va3mw

Sent from my iPad

> On Jul 5, 2019, at 7:16 AM, Conrad PA5Y <[hidden email]> wrote:
>
> Neither!
>
>
> I would buy a good transverter to use with a K3S. Two obvious choices.
>
>
> https://shop.kuhne-electronic.com/kuhne/en/shop/converter-transverte/transverter/TR+144++PRO++Transverter/?card=1621
>
> TR 144 - PRO, Transverter - Kuhne Electronic Amateur Radio Shop<https://shop.kuhne-electronic.com/kuhne/en/shop/converter-transverte/transverter/TR+144++PRO++Transverter/?card=1621>
> shop.kuhne-electronic.com
> Endkundenshop main_nav Produkte Meta-Description
>
>
>
> http://www.ha1ya.hu/htmkepek/me2t_pro3_spec.htm
>
> ME2T-PRO3 & ME2HT-PRO3 transverter specifications<http://www.ha1ya.hu/htmkepek/me2t_pro3_spec.htm>
> www.ha1ya.hu
> • Frequency Coverage: 144.0-146.0MHz band. • IF in/out Frequency : 28.0-30.0MHz, or 14.0-16.0MHz • LO frq stability: Low phase noise, 1ppm PDI or optional 0.5ppm AXTAL TCXO's! • I/O Impedance : 50 Ohm unbalanced • Input Voltage : 13.8VDC, +-5%, polarity mismatch, 10A -40dB EMI filter. • Power Consumption : 0.55A on RX, 5.5A on TX @30W out version, 10.5A @50W version.
> Both of these transverters will outperform the Elecraft transverter with respect to TX PN, IMD and RX IMD. They are both excellent, the HA1YA is considerably cheaper and that is what I chose, actually in my case the ME2T XP because I need 2 channels for Xpol EME. I have extensively tested all these combinations.
>
>
> The IC9700 is nice and convenient and quite reasonable but both the TX and RX performance is inferior to the K3S with either of the above transverters.
>
>
> 73
>
>
> Conrad PA5Y
>
>
>
>
> ________________________________
> From: [hidden email] <[hidden email]> on behalf of Kjeld Holm <[hidden email]>
> Sent: 04 July 2019 20:31
> To: Elecraft Reflector
> Subject: [Elecraft] Digital modes on 144MHz only
>
> Digital modes on 144MHz only
>
> I plan for a second station to use for digital modes on 144MHz only. If you look at performance only (no price, no ergonomics, no use outside digital modes on 144MHz) what would you prefer
>
> 1) K3/K3S with internal transverter
> 2) IC-9700
>
> In both cases I plan to use a 1kW amplifier.
>
> Vy 73 de OZ1CCM, Kjeld
> ______________________________________________________________
> 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
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> Post: mailto:[hidden email]
>
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Dimitry Borzenko

Re: Digital modes on 144MHz only

Hi All.
Internal transverter possible to use but with external BPF

de 4z5cp

------ Original Message ------
From: "Michael Walker" <[hidden email]>
To: "Elecraft Reflector" <[hidden email]>
Sent: 05.07.2019 14:43:36
Subject: Re: [Elecraft] Digital modes on 144MHz only

>Hi
>
>These are the Transverters I use.
>
>Very good quality and they can be 10mhz gps locked.
>
>
>http://www.q5signal.com/
>
>Mike va3mw
>
>
>Sent from my iPad
>
>> On Jul 5, 2019, at 7:16 AM, Conrad PA5Y <[hidden email]> wrote:
>>
>> Neither!
>>
>>
>> I would buy a good transverter to use with a K3S. Two obvious choices.
>>
>>
>> https://shop.kuhne-electronic.com/kuhne/en/shop/converter-transverte/transverter/TR+144++PRO++Transverter/?card=1621
>>
>> TR 144 - PRO, Transverter - Kuhne Electronic Amateur Radio Shop<https://shop.kuhne-electronic.com/kuhne/en/shop/converter-transverte/transverter/TR+144++PRO++Transverter/?card=1621>
>> shop.kuhne-electronic.com
>> Endkundenshop main_nav Produkte Meta-Description
>>
>>
>>
>> http://www.ha1ya.hu/htmkepek/me2t_pro3_spec.htm
>>
>> ME2T-PRO3 & ME2HT-PRO3 transverter specifications<http://www.ha1ya.hu/htmkepek/me2t_pro3_spec.htm>
>> www.ha1ya.hu
>> • Frequency Coverage: 144.0-146.0MHz band. • IF in/out Frequency : 28.0-30.0MHz, or 14.0-16.0MHz • LO frq stability: Low phase noise, 1ppm PDI or optional 0.5ppm AXTAL TCXO's! • I/O Impedance : 50 Ohm unbalanced • Input Voltage : 13.8VDC, +-5%, polarity mismatch, 10A -40dB EMI filter. • Power Consumption : 0.55A on RX, 5.5A on TX @30W out version, 10.5A @50W version.
>> Both of these transverters will outperform the Elecraft transverter with respect to TX PN, IMD and RX IMD. They are both excellent, the HA1YA is considerably cheaper and that is what I chose, actually in my case the ME2T XP because I need 2 channels for Xpol EME. I have extensively tested all these combinations.
>>
>>
>> The IC9700 is nice and convenient and quite reasonable but both the TX and RX performance is inferior to the K3S with either of the above transverters.
>>
>>
>> 73
>>
>>
>> Conrad PA5Y
>>
>>
>>
>>
>> ________________________________
>> From: [hidden email] <[hidden email]> on behalf of Kjeld Holm <[hidden email]>
>> Sent: 04 July 2019 20:31
>> To: Elecraft Reflector
>> Subject: [Elecraft] Digital modes on 144MHz only
>>
>> Digital modes on 144MHz only
>>
>> I plan for a second station to use for digital modes on 144MHz only. If you look at performance only (no price, no ergonomics, no use outside digital modes on 144MHz) what would you prefer
>>
>> 1) K3/K3S with internal transverter
>> 2) IC-9700
>>
>> In both cases I plan to use a 1kW amplifier.
>>
>> Vy 73 de OZ1CCM, Kjeld
>> ______________________________________________________________
>> 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
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>> 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]
>______________________________________________________________
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Martin

Re: Digital modes on 144MHz only

In reply to this post by Kjeld Holm

That's not quite right. The overall system noise is determined by the
preamp noise figure when mounted as close to the antenna as possible.
Cable losses (=noise) after the preamp can be neglected, as long as the
gain of the preamp is higher than the losses in subsequent components.
So the cable AFTER the preamp can be pretty lossy. OTOH, too much gain
from the preamp easily overdrives your transceiver's RX. A good balance
between gain vs. cable losses is mandatory. The noise figure of the
pramp is crucial.
If you are satisfied with your transverter's noise figure , mount it
close to the antenna via a short run low loss cable, if you can. This
saves the expenses for a preamp.

This applies to the RX path. I'm not talking cable quality or output
power for TX.

> Message: 15
> Date: Thu, 4 Jul 2019 17:11:58 -0500
> From: Bob McGraw K4TAX <[hidden email]>
> To: [hidden email]
> Subject: Re: [Elecraft] Digital modes on 144MHz only
>
> ..... Start with a mast mounted low noise preamp, then low loss
> feedline such as 7/8" hard-line, and such. Remember, loss in the
> feedline adds to receiver noise.
> ..........
>

--

Ohne CW ist es nur CB..

73, Martin DM4iM
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Wes Stewart-2

Re: Digital modes on 144MHz only

That isn't quite right either. The preamp gain must be much higher than the
following losses to minimize second stage degradation. (Line loss degrades the
NF of the second stage)

Wes N7WS

On 7/5/2019 5:35 AM, Martin wrote:

>
> That's not quite right. The overall system noise is determined by the preamp
> noise figure when mounted as close to the antenna as possible. Cable losses
> (=noise) after the preamp can be neglected, as long as the gain of the preamp
> is higher than the losses in subsequent components. So the cable AFTER the
> preamp can be pretty lossy. OTOH, too much gain from the preamp easily
> overdrives your transceiver's RX. A good balance between gain vs. cable losses
> is mandatory. The noise figure of the pramp is crucial.
> If you are satisfied with your transverter's noise figure , mount it close to
> the antenna via a short run low loss cable, if you can. This saves the
> expenses for a preamp.
>
> This applies to the RX path. I'm not talking cable quality or output power for
> TX.
>
>
> > Message: 15
> > Date: Thu, 4 Jul 2019 17:11:58 -0500
> > From: Bob McGraw K4TAX <[hidden email]>
> > To: [hidden email]
> > Subject: Re: [Elecraft] Digital modes on 144MHz only
> >
> > ..... Start with a mast mounted low noise preamp, then low loss
> > feedline such as 7/8" hard-line, and such. Remember, loss in the
> > feedline adds to receiver noise.
> > ..........
> >
>
>

Wes Stewart-2

Re: Digital modes on 144MHz only

In reply to this post by Jim Brown-10

The OP was talking about 144 MHz. For weak signal work I can't imagine not
using a mast-mounted preamp. Even with sub 1 dB NF devices (that we paid dearly
for when I was on EME) located in the shack, line loss is a killer.

Wes N7WS

On 7/4/2019 10:01 PM, Jim Brown wrote:
> In today's world, a mast-mounted preamp is a waste of effort for the vast
> majority of hams because circuit noise in the receiver is rarely the
> limitation on what we hear.

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Elecraft mailing list

Re: Digital modes on 144MHz only

In reply to this post by Wes Stewart-2

Our first commercial 11 metre dish earth station built in 1984 had a
4GHz 60dB gain, 33 Kelvin, electrically cooled two stage parametric LNA
at the feed horn. the cable to the receive system was LDF4-50 with 20dB
loss to a six port passive splitter.

The LNAs despite being pressurised constantly with dry air with a small
bleed hole had to be purged of frost every six months by turning the
cooling into heating and increasing the outflow of air. After 12 hours
of cool down they had to be retuned, pump frequency and power to achieve
60dB flat gain over 500MHz bandwidth. Times have changed.

Regards,

Mike VP8NO

On 05/07/2019 10:08, Wes wrote:

> That isn't quite right either. The preamp gain must be much higher than
> the following losses to minimize second stage degradation. (Line loss
> degrades the NF of the second stage)
>
> Wes N7WS
>
> On 7/5/2019 5:35 AM, Martin wrote:
>>
>> That's not quite right. The overall system noise is determined by the
>> preamp noise figure when mounted as close to the antenna as possible.
>> Cable losses (=noise) after the preamp can be neglected, as long as
>> the gain of the preamp is higher than the losses in subsequent
>> components. So the cable AFTER the preamp can be pretty lossy. OTOH,
>> too much gain from the preamp easily overdrives your transceiver's RX.
>> A good balance between gain vs. cable losses is mandatory. The noise
>> figure of the pramp is crucial.
>> If you are satisfied with your transverter's noise figure , mount it
>> close to the antenna via a short run low loss cable, if you can. This
>> saves the expenses for a preamp.
>>
>> This applies to the RX path. I'm not talking cable quality or output
>> power for TX.

Conrad PA5Y

Re: Digital modes on 144MHz only

In reply to this post by Wes Stewart-2

Wes is quite right.

There is a free program called AppCAD that allows system noise figure analysis for up to 7 cascaded stages. It is enlightening and you will understand the significance of each stage in no time just by plugging a few numbers in. Have a try its educational 😊

73

Conrad PA5Y

-----Original Message-----
From: [hidden email] <[hidden email]> On Behalf Of Wes
Sent: 05 July 2019 15:08
To: [hidden email]
Subject: Re: [Elecraft] Digital modes on 144MHz only

That isn't quite right either. The preamp gain must be much higher than the following losses to minimize second stage degradation. (Line loss degrades the NF of the second stage)

Wes N7WS

On 7/5/2019 5:35 AM, Martin wrote:

>
> That's not quite right. The overall system noise is determined by the
> preamp noise figure when mounted as close to the antenna as possible.
> Cable losses
> (=noise) after the preamp can be neglected, as long as the gain of the
> preamp is higher than the losses in subsequent components. So the
> cable AFTER the preamp can be pretty lossy. OTOH, too much gain from
> the preamp easily overdrives your transceiver's RX. A good balance
> between gain vs. cable losses is mandatory. The noise figure of the pramp is crucial.
> If you are satisfied with your transverter's noise figure , mount it
> close to the antenna via a short run low loss cable, if you can. This
> saves the expenses for a preamp.
>
> This applies to the RX path. I'm not talking cable quality or output
> power for TX.
>
>
> > Message: 15
> > Date: Thu, 4 Jul 2019 17:11:58 -0500
> > From: Bob McGraw K4TAX <[hidden email]>
> > To: [hidden email]
> > Subject: Re: [Elecraft] Digital modes on 144MHz only
> >
> > ..... Start with a mast mounted low noise preamp, then low loss
> > feedline such as 7/8" hard-line, and such. Remember, loss in the
> > feedline adds to receiver noise.
> > ..........
> >
>
>

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