[TenTec] Ten Tec Model 9420, AC power supply problem

[Richard Mortimore]

I used my 9420 PSU non-stop 1996 to 2003 with my Omni VI Plus, mainly contests and dxpeditions and they have been phenomenal.  We moved in 2005 and when settingt up I realised it had a problem, then it’s been in storage for a while. Right now I have done an initial investigation. It’s set-up for 240v here in the UK and both the 15A Line fuses are fine. The Linear and XCVR seem to respond to PWR ON, but neither work properly.

The good news is on the multi-pin Linear plug I get 14v for each of the Regulator boards, DC A, DC B, DC C and DC D and ground pairs. I also have 14v, the + Reg on pin 6.  But I don’t get the +14v/3A on pin 9, no surprise then that I have also lost the two phono outputs AUX  + 13.5v, Max 3A as well.

On the 4 way XCVR plug I am getting 14v on Pin 2, XCVR PWR (LO I), but nothing on Pin 1, XCVR PWR (HI I). 

Looking at the schematic I am on the Power Supply Control board,  The fuse F1 is good. I don’t see how I am getting XCVR PWR (LO I) but not XCVR PWR (HI I), however, on the component layout it looks like the XCVR PWR HI I comes straight off the board. I am also looking at the K3 relay which they share and Q7, I need to delve further but that’s as far as I’ve got.

I was trying to get on the Ten Tec website last night, right, all very sad. Anyway, I just wondered if anyone else has had this problem, or knows the solution.

73

Rich GW4BVJ