TX relay hang time

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TX relay hang time

VK7MA
Hi all,
is there a way I can increase the delay from PTT release to TX relay release (also external PTT)?
I am using a Hermes Lite 2.
The reason I ask is that I am seeing a SWR spike upon PTT release. Not much, but still there.
I am wondering if there is still some RF when the relay is released.
This is not really a issue when the antenna is tuned close to 1:1 but enough to trip the SWR protection in my amplifier if it is around 1.4:1 or so (Amplifier SWR protection is set at 2:1)
I also see a little spike when releasing PTT into a dummy load. Not every time but it still often enough.

Thanks in advance!

73
Martin.
VK7MA
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Re: TX relay hang time

ahlstromjc
Administrator
Please try increasing the "Keyup delay msecs" on the radio timing screen. That is supposed to generate the needed delay. Let me know if it doesn't work.

Jim
N2ADR
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Re: TX relay hang time

VK7MA
Hi Jim,
thanks for your reply.
I tried increasing the keyup delay. This does not seen to affect relay timing (and the issue), just the quisk transition back to rx..

73

Martin
VK7MA
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Re: TX relay hang time

ahlstromjc
Administrator
OK, I will look into it.

Jim
N2ADR
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Re: TX relay hang time

ahlstromjc
Administrator
In reply to this post by VK7MA
Yes, I see the problem. The HermesLite adds the delay to the hardware CW key, but not to the software key. I will fix this in the next release.

Jim
N2ADR
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Re: TX relay hang time

VK7MA
Many thanks Jim.

Take care.

73

Martin
VK7MA