Hi Tim
You need to try employing a "contact wetting circuit"
Install a .01 Capacitor in series with the transceiver antenna in to the
amp.
Put a 470 ohm 2 watt resistor from the relay side to +12-24 volts DC.
Then install a 1k 2 watt resistor between the antenna and ground via a spare
relay contact on the antenna change over relay or another relay in parallel
to the RF one.
It will keep a small flow of current during receive to ensure the contacts
make.
I have in the past also turned a vacuum relay upside down and increased the
current through the contacts and pulsing the relay.
This has also fixed the problem.
Good luck
Cheers Gary
> ZL3SV
>
>
>
> ----- Original Message -----
> From: "N3XX" <n3xx@charter.net>
> To: <Amps@contesting.com>
> Sent: Thursday, September 11, 2008 11:23 AM
> Subject: [Amps] Vacuum relay adjustment?
>
>
>> Hope someone on the list can help with information about a vacuum relay I
>> have. I'm working on getting an LK-800 amp back in good working
>> condition,
>> and one of the problems it has is a T/R vacuum relay that won't go back
>> to
>> receive after transmitting. If I tap on the relay, it does go back to
>> receive. The relay is a Jennings RJ1A-26S. On this relay is a screw
>> that
>> looks as if it is for adjustment, but I don't know what it adjusts. I'm
>> guessing it has to be either contact spacing or spring tension. I hope
>> it's
>> for spring tension, and by adjusting this screw I can put a little more
>> tension on the spring, and it will return to receive when finished
>> transmitting.
>> Just thought I would check here and see if someone knows what the screw
>> is
>> for before I start turning it, not knowing what it is supposed to do.
>> Thanks for any info.
>>
>> 73,
>> Tim - N3XX
>>
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>
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