It's the same through the headphone socket. The new inputs were just rigged quickly to test everyone's theory that the inputs were faulty/dirty.

Hope these help...to save you a bit of time decoding. O 1  O 2 O 3 on the pcb is where the inputs connect to the board. 1 is the grey wire 2 is the ground and 3 is the blue wire. 3 connects to R10 and 1 connects to one leg of what I think is a transistor. The soldered side looks awful I know, but the old capacitors had the legs soldered along the tracks and were difficult to remove without damage. I've checked these connections and they seem fine. I may have connected something up incorrectly but I don't think so.

Thanks for your help so far

steve

It's amazing that people are willing to spend time to help keeping these old amps going. In particular how patient and generous people who know more about these things than i do.
Here are some more pics

Hi all, I replaced both input sockets and the wiring to the pcb. No change though I'm afraid. The really unusual thing is how loud the noise is when you plug in or pull out a jack. The amplifier seems to be working but something definitely wrong on the input side. The amp has a Volume (gain) and a master volume. Is there anything in the gain circuit that could have failed or should I just keep resoldering connections on the pcb.

steve

Thanks I'll try that and report back.

Hi I wonder if anybody can help me with a problem with my HH micro 30. I have been using valve amps for sometime now but I've had this amp for 30 years now and it's got a bit of sentimental value if little actual value. My son was using it until recently when he brought it to me saying it wasn't working. I had a quick look and noticed the power smoothing caps looked dodgy and the two small fuses had blown. I replaced the power caps with the nearest equivalent (63v instead of 45v) and one of the rectifier diodes which I thought was giving an odd reading. New fuses and the amp came back to life. I thought that the volume was a bit lower than I remembered so I replaced some of the other caps. The amp seemed ok and I used it for a couple of gigs to give it a bit of a road test. However last time I came to use it I could hardly get any volume out of it at all. Cleaned all of the pots and retested some of my new joints but can't find anything obvious. The new caps were a big bigger so are a bit of a squeeze.

I'm really not very experienced with electronics, although I can follow instructions.

Another symptom is that the amp makes a loud pop when removing the jack from either the hi or low input

Any thoughts please