[Amps] Alpha 77 start up

[Jan Ditzian]

I just received an Alpha 77 Dx, modified as a two-holer, as a gift (I 
have very understanding friends).  However, it came with a problem--it 
does not work. The startup light does not come on.  The previous owner 
sent a board back to Alpha to fix this problem, and their paperwork 
shows that they repaired it and then tested it in an Alpha 77Sx, which 
is equivalent to the two-hole modified Dx, and it worked.  However, 
after putting the board into this rig, the problem remains.  Since I am 
new to this amp, and did not have it integrated into my station, I did 
the following checks:

I set up the amp with no exciter, but with power, and the fan comes on 
and the voltage goes to about 2600 volts. I followed the regular startup 
procedure and, sure enough, the light does not come on after six minutes 
(it is supposed to take about 3minutes).  I then put a cable into the 
relay jack on the back, repeated the above process, went ahead and put 
the amp into CW/low power mode after a six-minute wait, and then shorted 
the relay cable.  I did not hear a relay click--nothing happened.

Can someone help me to isolate the problem with this amp?  Until this 
happened, the previous owner (the donor of the amp) was using it without 
a problem.  There was no cataclysmic event that preceded the failure to 
start up.

I can imagine problems like bad contacts on the board connector, or 
perhaps the failure of another relay somewhere.

Thank you,

Jan, KX2A