Vintage: Heathkit SB-104 relay clicks no transmit.......help?

[Retroradio]

As the title says my SB-104 is not transmitting on Low or High power
The jumper from pin 2 to 5 is in place on the octal plug
The VFO is jumpers as per the setup instructions
Have tried 3 different microphones and nada.
Everything else is working.
Any suggestions would be great.

Cheers

 

[Retroradio]

Bump

Reset everything today..Key the mic....TX relay clicks...no output.
Anyone?

 

[WB9YBM]

I've noticed this in other radio equipment as well. Here's the cause: since the electronics operate faster than the mechanical stuff (in this case the relay) the transmit signal will be present a few micro- ("milli-"?) seconds before the relay mechanically swings to the other set of contacts, causing a momentary arcing across the contacts. Carefully burnishing the contacts will cure this (most of the time). Upgrading to a faster acting "mercury wetted" relay (or other RF-specific relay) will reduce or eliminate the problem.

 

[Retroradio]

Ill have to take it apart again and have a look. I really need to get this working as its been too long with it sitting there...lol
No luck this week as my old trusty Kenwood TS-430S is now only doing 30 watts...