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Dual Ptt

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Ralph S

Dual Ptt

Hi all

I need to be able to key the KPA500 & KAT500 from both a Yaesu 1000mp and my K3.

I assume (I know don't assume) I can use diodes to isolate both radios.

Any thoughts?

Ralph, W7HSG/AFA9RT
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Don Wilhelm

Re: Dual Ptt

Ralph,

If you must switch between the two rigs, you will need to connect the K3
for basic mode - only the KEYOUT line and not AUX cables.

Although you might derive a diode "OR" circuit, I assume you will also
need to switch the RF path - so I suggest that a hard contact switch or
relay will be more trouble free and more free of operator errors caused
by keying the amp and ATU from the wrong transceiver.

You may also want to switch the microphone/PTT and/or paddles from one
transceiver to another. Easily done with a switch or relay. I strongly
believe in the KISS principle.

73,
Don W3FPR

On 11/3/2018 2:21 PM, Ralph S. Turk wrote:

> Hi all
>
> I need to be able to key the KPA500 & KAT500 from both a Yaesu 1000mp and my K3.
>
> I assume (I know don't assume) I can use diodes to isolate both radios.
>
> Any thoughts?
>
> Ralph, W7HSG/AFA9RT
> ______________________________________________________________
> 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]
>

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Bob McGraw - K4TAX

Re: Dual Ptt

In reply to this post by Ralph S

I basically do the same with different radios.   The K3S is connected to
the KAT500 and then through the KPAK3AUX cable to the KPA500.   The
other radio has a Amp Key output basically an open collector to ground
which I connect to the PA Key input.   Either radio will key the KPA500
and no switching or changes required. Just cables and connectors.
Adding the KAT500 requires a second KPAK3AUX cable and slightly
different wiring configuration. However, with either radio, no other
changes required.   Just be sure you have the correct drive power set
and TUNE power set for each radio before hitting the PTT switch.

All this is very easy to accomplish with the cables and connectors
provided by Elecraft. The worst part is that hams "over think" the
solution.

73

Bob, K4TAX

On 11/3/2018 1:21 PM, Ralph S. Turk wrote:

Don Wilhelm

Re: Dual Ptt

Bob,

That is a simple solution, but how do you handle the RF output of both
transceiver to the single RF in on the amplifier?

The only caution I can give of with a configuration like that is for the
operator who uses voice modes with VOX turned on.
Most ham mics are wired for VOX operation - in other words, the mics are
'live'. For those who use speakers too, the mic on the 'not in use' can
pick up the sound from the 'live' transceiver speaker and set it in
transmit mode.

The use of headphones will likely cause no problems, but the combination
of VOX ON with speakers live can cause a problem for voice modes.

My preference is for hard switching to eliminate a lot of "strange
happenings" - besides, I like to feel I am in control of such things.
Such a switching arrangement can be easily built, but there are several
SO2R boxes that will accomplish the same thing.

73,
Don W3FPR

On 11/5/2018 3:30 PM, Bob McGraw K4TAX wrote:

> I basically do the same with different radios.   The K3S is connected to
> the KAT500 and then through the KPAK3AUX cable to the KPA500.   The
> other radio has a Amp Key output basically an open collector to ground
> which I connect to the PA Key input.   Either radio will key the KPA500
> and no switching or changes required. Just cables and connectors. Adding
> the KAT500 requires a second KPAK3AUX cable and slightly different
> wiring configuration. However, with either radio, no other changes
> required.   Just be sure you have the correct drive power set and TUNE
> power set for each radio before hitting the PTT switch.
>
> All this is very easy to accomplish with the cables and connectors
> provided by Elecraft. The worst part is that hams "over think" the
> solution.
>
> 73
>
> Bob, K4TAX
>
>
> On 11/3/2018 1:21 PM, Ralph S. Turk wrote:
>> Hi all
>>
>> I need to be able to key the KPA500 & KAT500 from both a Yaesu 1000mp
>> and my K3.
>>
>> I assume (I know don't assume) I can use diodes to isolate both radios.
>>
>> Any thoughts?
>>
>> Ralph, W7HSG/AFA9RT
>> ______________________________________________________________
>> 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]
>>
>
>
> ______________________________________________________________
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> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
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Bob McGraw - K4TAX

Re: Dual Ptt

I use a manual 2 x 1 coax switch to switch between 2 radios to one amp input. As to VOX it is always off unless I turn it on. I usually only use one radio at a time.

Bob, K4TAX

Sent from my iPhone

> On Nov 6, 2018, at 9:09 AM, Don Wilhelm <[hidden email]> wrote:
>
> Bob,
>
> That is a simple solution, but how do you handle the RF output of both transceiver to the single RF in on the amplifier?
>
> The only caution I can give of with a configuration like that is for the operator who uses voice modes with VOX turned on.
> Most ham mics are wired for VOX operation - in other words, the mics are 'live'. For those who use speakers too, the mic on the 'not in use' can pick up the sound from the 'live' transceiver speaker and set it in transmit mode.
>
> The use of headphones will likely cause no problems, but the combination of VOX ON with speakers live can cause a problem for voice modes.
>
> My preference is for hard switching to eliminate a lot of "strange happenings" - besides, I like to feel I am in control of such things.
> Such a switching arrangement can be easily built, but there are several SO2R boxes that will accomplish the same thing.
>
> 73,
> Don W3FPR
>
>> On 11/5/2018 3:30 PM, Bob McGraw K4TAX wrote:
>> I basically do the same with different radios. The K3S is connected to the KAT500 and then through the KPAK3AUX cable to the KPA500. The other radio has a Amp Key output basically an open collector to ground which I connect to the PA Key input. Either radio will key the KPA500 and no switching or changes required. Just cables and connectors. Adding the KAT500 requires a second KPAK3AUX cable and slightly different wiring configuration. However, with either radio, no other changes required. Just be sure you have the correct drive power set and TUNE power set for each radio before hitting the PTT switch.
>> All this is very easy to accomplish with the cables and connectors provided by Elecraft. The worst part is that hams "over think" the solution.
>> 73
>> Bob, K4TAX
>>> On 11/3/2018 1:21 PM, Ralph S. Turk wrote:
>>> Hi all
>>>
>>> I need to be able to key the KPA500 & KAT500 from both a Yaesu 1000mp and my K3.
>>>
>>> I assume (I know don't assume) I can use diodes to isolate both radios.
>>>
>>> Any thoughts?
>>>
>>> Ralph, W7HSG/AFA9RT
>>> ______________________________________________________________
>>> 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: Dual Ptt

Bob,

Since you do have to turn a switch, my preference would be to build a
switch to change the KEYOUT line and also operate a relay in the coax
line. I think it give a bit more protection from "tired operator syndrome".
Additional switch contacts could switch microphone AF and PTT between
the transceivers and other contacts could switch key and paddle lines.
But then that is my preference. I use RS-232 A/B switches for things
like that. The ones that handle DB25 connectors have 25 switch contacts
- plenty for whatever you want to switch.

73,
Don W3FPR

On 11/6/2018 10:25 AM, Bob McGraw K4TAX wrote:

> I use a manual 2 x 1 coax switch to switch between 2 radios to one amp input. As to VOX it is always off unless I turn it on. I usually only use one radio at a time.
>
> Bob, K4TAX
>
>
> Sent from my iPhone
>
>> On Nov 6, 2018, at 9:09 AM, Don Wilhelm <[hidden email]> wrote:
>>
>> Bob,
>>
>> That is a simple solution, but how do you handle the RF output of both transceiver to the single RF in on the amplifier?
>>
>> The only caution I can give of with a configuration like that is for the operator who uses voice modes with VOX turned on.
>> Most ham mics are wired for VOX operation - in other words, the mics are 'live'. For those who use speakers too, the mic on the 'not in use' can pick up the sound from the 'live' transceiver speaker and set it in transmit mode.
>>
>> The use of headphones will likely cause no problems, but the combination of VOX ON with speakers live can cause a problem for voice modes.
>>
>> My preference is for hard switching to eliminate a lot of "strange happenings" - besides, I like to feel I am in control of such things.
>> Such a switching arrangement can be easily built, but there are several SO2R boxes that will accomplish the same thing.
>>
>> 73,
>> Don W3FPR
>>
>>> On 11/5/2018 3:30 PM, Bob McGraw K4TAX wrote:
>>> I basically do the same with different radios. The K3S is connected to the KAT500 and then through the KPAK3AUX cable to the KPA500. The other radio has a Amp Key output basically an open collector to ground which I connect to the PA Key input. Either radio will key the KPA500 and no switching or changes required. Just cables and connectors. Adding the KAT500 requires a second KPAK3AUX cable and slightly different wiring configuration. However, with either radio, no other changes required. Just be sure you have the correct drive power set and TUNE power set for each radio before hitting the PTT switch.
>>> All this is very easy to accomplish with the cables and connectors provided by Elecraft. The worst part is that hams "over think" the solution.
>>> 73
>>> Bob, K4TAX
>>>> On 11/3/2018 1:21 PM, Ralph S. Turk wrote:
>>>> Hi all
>>>>
>>>> I need to be able to key the KPA500 & KAT500 from both a Yaesu 1000mp and my K3.
>>>>
>>>> I assume (I know don't assume) I can use diodes to isolate both radios.
>>>>
>>>> Any thoughts?
>>>>
>>>> Ralph, W7HSG/AFA9RT
>>>> ______________________________________________________________
>>>> 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]
>
>

Ralph S

Re: Dual Ptt

In reply to this post by Don Wilhelm

Hi all.
I use hard switching between the radios to the input of the KPA500 & KAT500. The Yaesu has +12vdc on the Ptt output except when it is transmitting, then it goes to ground. Just looking for the simple way to
switch PTT between the Yaesu 1000mp and the K3 as it goes to the KPA500 & the KAT500.
Ralph, W7hsg/AFA9RT

> On November 6, 2018 at 8:09 AM Don Wilhelm <[hidden email]> wrote:
>
>
> Bob,
>
> That is a simple solution, but how do you handle the RF output of both
> transceiver to the single RF in on the amplifier?
>
> The only caution I can give of with a configuration like that is for the
> operator who uses voice modes with VOX turned on.
> Most ham mics are wired for VOX operation - in other words, the mics are
> 'live'. For those who use speakers too, the mic on the 'not in use' can
> pick up the sound from the 'live' transceiver speaker and set it in
> transmit mode.
>
> The use of headphones will likely cause no problems, but the combination
> of VOX ON with speakers live can cause a problem for voice modes.
>
> My preference is for hard switching to eliminate a lot of "strange
> happenings" - besides, I like to feel I am in control of such things.
> Such a switching arrangement can be easily built, but there are several
> SO2R boxes that will accomplish the same thing.
>
> 73,
> Don W3FPR
>
> On 11/5/2018 3:30 PM, Bob McGraw K4TAX wrote:
> > I basically do the same with different radios.   The K3S is connected to
> > the KAT500 and then through the KPAK3AUX cable to the KPA500.   The
> > other radio has a Amp Key output basically an open collector to ground
> > which I connect to the PA Key input.   Either radio will key the KPA500
> > and no switching or changes required. Just cables and connectors. Adding
> > the KAT500 requires a second KPAK3AUX cable and slightly different
> > wiring configuration. However, with either radio, no other changes
> > required.   Just be sure you have the correct drive power set and TUNE
> > power set for each radio before hitting the PTT switch.
> >
> > All this is very easy to accomplish with the cables and connectors
> > provided by Elecraft. The worst part is that hams "over think" the
> > solution.
> >
> > 73
> >
> > Bob, K4TAX
> >
> >
> > On 11/3/2018 1:21 PM, Ralph S. Turk wrote:
> >> Hi all
> >>
> >> I need to be able to key the KPA500 & KAT500 from both a Yaesu 1000mp
> >> and my K3.
> >>
> >> I assume (I know don't assume) I can use diodes to isolate both radios.
> >>
> >> Any thoughts?
> >>
> >> Ralph, W7HSG/AFA9RT
> >> ______________________________________________________________
> >> 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
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> Message delivered to [hidden email]

Bob Wilson, N6TV

Re: Dual Ptt

In reply to this post by Bob McGraw - K4TAX

On Mon, Nov 5, 2018 at 12:32 PM Bob McGraw K4TAX <[hidden email]>
wrote:

> I basically do the same with different radios. The K3S is connected to
> the KAT500 and then through the KPAK3AUX cable to the KPA500. The
> other radio has a Amp Key output basically an open collector to ground
> which I connect to the PA Key input.

That's a very convenient way to do it, but connecting the radio directly to
PA KEY on the KPA500 bypasses an important safety feature of the KAT500,
which is designed to OPEN the PA KEY line while it is tuning. So I'd
recommend connecting the other radio's Amp Key output to the PTT RLY (in)
connector of the KAT500, and the PTT RLY (out) of the KAT500 to the KPA500
PA KEY. This places the KAT500 in SERIES between the transceiver's KEY OUT
and the KPA500's KEY IN.

This is well documented in Figures 2, 3, and 4 in the KAT500 Owner's Manual
<ftp://ftp.elecraft.com/KAT500/Manuals%20Downloads/E740183%20KAT500%20Owner's%20Manual-%20Rev%20C6.pdf>
.

73,
Bob, N6TV
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Bob McGraw - K4TAX

Re: Dual Ptt

Excellent point Bob. I'd not thought about that approach.

Thanks

73

Bob, K4TAX

On 11/7/2018 5:01 PM, Bob Wilson, N6TV wrote:

> On Mon, Nov 5, 2018 at 12:32 PM Bob McGraw K4TAX <[hidden email]>
> wrote:
>
>> I basically do the same with different radios. The K3S is connected to
>> the KAT500 and then through the KPAK3AUX cable to the KPA500. The
>> other radio has a Amp Key output basically an open collector to ground
>> which I connect to the PA Key input.
>
> That's a very convenient way to do it, but connecting the radio directly to
> PA KEY on the KPA500 bypasses an important safety feature of the KAT500,
> which is designed to OPEN the PA KEY line while it is tuning. So I'd
> recommend connecting the other radio's Amp Key output to the PTT RLY (in)
> connector of the KAT500, and the PTT RLY (out) of the KAT500 to the KPA500
> PA KEY. This places the KAT500 in SERIES between the transceiver's KEY OUT
> and the KPA500's KEY IN.
>
> This is well documented in Figures 2, 3, and 4 in the KAT500 Owner's Manual
> <ftp://ftp.elecraft.com/KAT500/Manuals%20Downloads/E740183%20KAT500%20Owner's%20Manual-%20Rev%20C6.pdf>
> .
>
> 73,
> Bob, N6TV
> ______________________________________________________________
> 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]
>