[TenTec] Tentec XCVR Keying Loop and Amp Supply Amp Question?

[Doug Smith]

Dennis,

Does your keyer have a relay output or an open collector output?

I have the Amp Supply LK-500ZC amp with the QSK option and the manual (page 7) 
states that the Key In jack must be connected to a "bug, hand key or keyer 
with a Reed Relay".  I've never been able to key the amp's QSK line with 
anything with a solid state output.

That being said, I am running QSK by connecting the Omni-VII Amp Key line to 
the RLY input on the amp and running the amp in VOX (not QSK) mode.

Using the RLY input, the LK-500ZC switches to transmit and is ready for RF at 
8.5 milliseconds.  The Omni-VII Amp Key line goes to ground 15 milliseconds 
before RF is produced.  So, the key down timing is good.  On key up, the 
Omni-VII Amp Key line stays at ground for 8 milliseconds after RF output 
decays to zero.  The amp switches back to receive in 5.2 milliseconds.  So, 
the key up timing is good.

So, for my Omni-VII and my LK-500ZC a direct connection between the rigs Amp 
Key line and the amps RLY input works very well.  Of course, your mileage may 
vary and you'd be well advised to make some measurements rather than just 
using the figures I've measured here..

73,
-Doug, W7KF


> ----- Original Message ----- 
> From: "Brickey, Dennis" <dbrickey at eastman.com>
>> I recently acquired an Amp Supply LK-500NTC with vacuum relay QSK.