Power supply faulty - gone high voltage.

Equipment
21

Just binned a load of those type PSUs at work.

22

Not worth the cost of repair Simon and especially if someone has already been in there and “repaired” it earlier.
Time to buy a replacement and bin this one I think.

73 Ed.

1 Like
23

Hi Peter

Reminds me of when I was a young engineer back in the early 80’s. In those days there was still a drawing office who had to produce drawings of everything, including components. We would regularly have fun at their expense by submitting spoof components. They would usually draw them up and send it back for checking - I never worked out if they did it to humour us, or they really had no idea.

A couple of the best

  • The WOM or Write-Only Memory. You can write as much data as you like into it but never get it back.

  • The SED or Smoke Emitting Diode. Self explanatory …

  • The negative 100 ohm resistor. We actually built one to prove it worked.

Rick

5 Likes
24

That version, PL-18 is not the best to mod. Whilst getting the voltage from 12.2V to 13.8 involves adding or removing a resistor, it tends to go into overvoltage protect when set to 13.8 and you pull a regularly varying current such as a big SSB signal. You can set the volts to 13.4 and it’s cool. Or you can tweak the overvolts pot but that is not well documented.

The HSTNS-PD14 and PD18 versions are better documented and are worth seeking out. More expensive now they are better documented.

1 Like
25

Not sure of the exact versions we binned, but we do have a fair few HP servers(Slowly being wound down in favour of ‘to the cloud’. Next time I am binning some, I will take a look.

1 Like
26

All of them can be modified for amateur use. But it’s easiest when someone has a nice set of instructions and pictures. :slight_smile:

1 Like
27

Makes life a lot easier with instructions.

28

Thanks for all the advice & help.

We’ve picked up a replacement power supply to get back on air as chasers.

Thanks & 73, Simon & Nic.

2 Likes
29

Thanks for the final news Simon and thanks for taking us all along on the investigation to find out what happened. I am sure some of us will see the same problem with ageing PSUs in the future and now we can draw on your experience and the advice given here as a group to help us decide whether a repair or a replacement is the better option.

If you have HF I hope to work you soon - once the HF bands get back to normal!

73 Ed.

2 Likes