[Amps] Fwd: Re: Modern rig amplifier keying

Stan Gammons s_gammons at charter.net
Sun Jul 21 17:09:15 EDT 2019

Hi Bob,

Thanks. That was one of the last pieces to this conversion that I've 
taken forever to finish. Still undecided on how I want to do the tuned 
input circuits. The amp is actually an in between model. It's labeled a 
Clipperton-L, but it's actually a Cliiperton QRO. It has the center 
tapped filament and the tubes sockets and tuned inputs are on a PCB that 
mounts vertically to the divider panel. I thought about just copying the 
existing PCB portion that has the tuned inputs and re-using the existing 
parts.  I also thought about building new tuned inputs with adjustable 
coils. That would require a little more work though. Maybe I'll get this 
project done before I become an SK.

Yeah, when I looked at the specs for the TS-590SG, it led me to believe 
10 ma using the RL pin was all it would switch.  Thanks for sharing the 
info on mechanical relay!



On 7/21/2019 2:27 PM, Bob Wilson, N6TV wrote:
> Stan,
> Congratulations on getting this to work, but like most other modern 
> radios, the TS-590SG has an option to enable an internal mechanical 
> relay to key amplifiers that required more than 10ma.  Unfortunately, 
> it is poorly documented.
> See footnote 2 on page 55:
>     *2 Mechanical Relay Operation.  You can switch the signal of the
>     high voltage like a vacuum tube linear amplifier.  It is possible
>     to control the terminal voltage of TL-922 (approximately -140 V).
> First set both Linear Amp menus No. 59 (HF) and 60 (VHF) to Option 3 
> to enable the TS-590SG mechanical relay.  Also rewire the amplifier's 
> KEY IN to TS-590SG REMOTE Connector Pin 4 (MKE) instead of to Pin 7 
> (RL), which is only used for silent solid-state keying of more modern 
> amplifiers that require low current.  REMOTE Pin 2 is ground / 
> shield.  See diagram on Page 73.
> The KEY OUT connector of an Elecraft K3/K3S (RCA) can key up to 200VDC 
> at 5A (with no noisy relay).  It also has a KEYOUT-LP pin on the ACC 
> connector rated at only 10ma max, for more modern amps.  No menu 
> changes needed except TX DLY.
> 73,
> Bob, N6TV
> On Sun, Jul 21, 2019 at 7:45 AM Stan Gammons <s_gammons at charter.net 
> <mailto:s_gammons at charter.net>> wrote:
>     Someone ask what amp and rig. The amp is a Clipperton-L I
>     converted to a
>     pair of GI-7BT tubes. Relay is 12 volts and draws around 100 ma
>     when the
>     coil is energized.  I haven't decided on a rig, but was considering a
>     TS-590SG. I see 10 milliamps is all the TS-590SG will switch. So, I
>     decided to re-engineer a Harbach SK-401 I had left over after
>     installing
>     a ES4L4-B in my L-4B.  Around 15 volts was the minimum voltage the
>     SK-401 would operate at, so I swapped R1 and R2, 22k 1/4 w resistors,
>     with 18K 1/4 watt resistors and the circuit will now operate with 12
>     volts, possibly lower though I didn't try it. I measured .788
>     milliamps
>     to trigger the SK-401, so I think it will be fine to use with the
>     TS-590SG or possibly any other modern rig. The youngest rig I have
>     is a
>     Omni VI.
>     Thanks again for all of the replies.
>     73
>     Stan
>     KM4HQE
>     On 7/20/2019 9:34 AM, Glen Zook wrote:
>     > Having 12-volts on the keying circuit (actually, usually,
>     13.8-volts)
>     > is very common and I don't know of any "modern" transceiver that
>     > cannot handle the voltage.
>     >
>     > Glen, K9STH
>     >
>     > Website: https://k9sth.net
>     >
>     >
>     > On Saturday, July 20, 2019, 08:32:43 AM CDT, Stan Gammons
>     > <s_gammons at charter.net <mailto:s_gammons at charter.net>> wrote:
>     >
>     >
>     > How much voltage will modern rigs tolerate on the keying
>     circuit? I have
>     > an older amp that has a 12 volt relay. Will that fry the keying
>     circuit
>     > of a modern rig?
>     >
>     >
>     > 73
>     >
>     > Stan
>     > KM4HQE

More information about the Amps mailing list