Last week I bought a Murphy U198H which was in something of a state.
I quickly found that neither pole of the main switch was making but after getting the jump-leads 'round it it was still silent. I then found that two of the three wires had come of the OPT and I couldn't make sense of where they went.
Over the w/end I had a proper look and sorted that out and it worked.
The next thing was to see if the UL41 output valve was leaking: it was, well and truly.
As these are darned expensive this set went on the Long Term/Source or Bits list. For what I'd paid for it I was still satisfied with it.
Yesterday somebody advised me to try a UL84 as this is electrically the same but not prone to leaks. By shear chance I'd got one salvaged from an old Dansette-type gramophone twenty-odd years ago. This is the old problem of hording 'rubbish' and then it proving useful which just encourages the habit. One of my first posts on The Forum had been for help in identifying this so that assistance has come in very useful.
I tried it this morning and it worked very well. It's also far more interesting and satisfying than just plugging a new correct valve in.
Here's the pin-outs in case anybody else is interested:-
I'm really impressed by the sound quality as it's only had THAT capacitor changed and the speaker is quite small, by valve radio standards, and it isn't in any sort of enclosure. It's certainly worth proceeding with the other bits.
- Joe
I quickly found that neither pole of the main switch was making but after getting the jump-leads 'round it it was still silent. I then found that two of the three wires had come of the OPT and I couldn't make sense of where they went.
Over the w/end I had a proper look and sorted that out and it worked.
The next thing was to see if the UL41 output valve was leaking: it was, well and truly.
As these are darned expensive this set went on the Long Term/Source or Bits list. For what I'd paid for it I was still satisfied with it.
Yesterday somebody advised me to try a UL84 as this is electrically the same but not prone to leaks. By shear chance I'd got one salvaged from an old Dansette-type gramophone twenty-odd years ago. This is the old problem of hording 'rubbish' and then it proving useful which just encourages the habit. One of my first posts on The Forum had been for help in identifying this so that assistance has come in very useful.
I tried it this morning and it worked very well. It's also far more interesting and satisfying than just plugging a new correct valve in.
Here's the pin-outs in case anybody else is interested:-
I'm really impressed by the sound quality as it's only had THAT capacitor changed and the speaker is quite small, by valve radio standards, and it isn't in any sort of enclosure. It's certainly worth proceeding with the other bits.
- Joe
