Back to the PYE PE-34 ... looks like nobody was able to help with a schematic. The bad socket for the EF22 was replaced a few weeks back, so its random screams and cutting-out have been fixed.

The power switch wasn't wired up properly, so it didn't do anything. It had been bypassed at the transformer taps. Someone had disconnected the wires from the speaker transformer to the back panel and repurposed them as power wires. I moved the wires back to their original function.

The volume control was only 250K, so that I guess explains a certain loss of volume. I replaced it with a 500K control. There's still a hole for the missing tone control arrangement, without a schematic it's not really possible to know how it should be hooked up, so I decided to do nothing about it.

Next, I replaced the 2x 1M resistors on the EM34 socket, both were open circuit. Then I fitted a EM34 valve and made sure it worked.

Just above the EM34 is a dial lamp which had always been troublesome, so I finally fixed it properly.

As noted above, the wrong speaker was in the radio, so I took the one from the other PYE which is not working. This speaker has the proper plugs for the back panel.

Finally I could put the radio back in its wooden case. Then I found a suitable back cardboard cover in a box and put it on.

Knobs were found and fitted, and a final test done. All the bands are working well. The only only problem is the tuning indicator - it's drowned out by the brightness of the dial lamps, in particular the one that I had just fixed. Oh well. At least one more radio has been rescued from the scrap heap.

I wasn't expecting to add to this topic, but since it's cricket season, with the T20 World Cup being held here, various radios have been used overtime so I could listen to it all. Last week, 2 of them failed on the same day. Today was the day to fix them.

First radio, a Mullard MAS1110A - valves: 6AN7, 6N8, 6N8, 6M5, EZ82. There's no schematic to be found, but it's quite similar to the MAS1110 apart from one valve, the tone switch, and a few component values. The first thing with these radios is to replace C17 (30pf) with a 1.5pf cap. This fixes the problem of it sounding like it's buried under a pile of clothes. This radio had already been modified.

The radio sits in the lounge room next to my Kriesler 11-99, and is used to monitor the internal radio station. A few weeks ago it started crackling, and last week I noticed the sound had stopped, and only the 11-99 was working. On the bench it worked on my station, but after tuning away it was silent for a few minutes, before the AGC eventually adjusted itself. All the valves are the "innoval" type, so I cleaned all the pins. After staring at the AGC parts for a bit, I thought that a resistor could be missing, so I downloaded the MAS1110 schematic and found that I was right. There's a pair of 2M resistors, but one was missing and the other had gone high. Also, the 2 diodes on the 6N8 were touching sometimes (at the valve socket), which probably accounted for the crackle. After fixing this and adding new parts, the AGC problem was fixed. Then, I found another problem - turning up the volume muted the sound. I've had this before - the components around the first AF amp need to be checked. I replaced a leaky cap on the volume control, and the anode load resistor, and that was fixed. The radio was returned to its position next to the 11-99 in fully working condition.

Second radio, a Philips 224 that lives on a cupboard in the garage and had only recently been repaired. Valves are the usual ones in small Philips radios: 6AN7, 6BH5, 6BD7, 6M5, 6V4. It worked fine on the internal station, but as soon as I tuned away, it started motorboating. Pulling the 6AN7 out stopped the noise, but it started again when a replacement was plugged in, before it even heated up. After poking here and there I noticed there was no RF bypass cap on the HT, so I added one (47nF) and the problem was immediately solved. I guess the chassis-mounted electro is on the way out, but I couldn't be bothered to replace it. Also, every radio should have a proper RF bypass cap. The radio works well after that. The only thing of worry is that the power transformer gets very hot after a while.

So, a couple of fairly easy repairs. I took my time because if you rush things mistakes can happen.

Many a radio were originally purchased for the purpose of listening to the cricket.

The radio from post #88 made a reappearance on the bench. I have 2 radios that use a 2A5 output valve, but only one working 2A5. I've been looking for another for years but without luck.

Under a pair of old gardening gloves I found 2 valves, and one of them was a faulty 2A5 that I thought I'd lost years ago. It didn't light up though, so I used my new 40 watt soldering iron to redo the heater connections on the valve base. Conduction was achieved, so I plugged it into the radio to see what happens. This valve has an open top, so you can see inside the working area. It lit up slowly, but no sound. A purple fog began to form inside. This slowly became more intense, and still no sound. I switched the radio off at the wall and the 2A5 flashed over. So I guess it's gassy and no use.

So, in the end, I'm still looking for another 2A5 that works..

2A5 became 6F6. I have a distinct feeling that I saw a 2A5 in an unsorted (most are) collection from a deceased estate, whist foraging for a 6J8 for the Cadet M5 that went home today.

Will check it out. Best I can do is an emission tube tester for them (VCT).

So, in the end, I'm still looking for another 2A5 that works.

Are you a member of the HRSA? If so, try the valve bank.

Found the tube where I thought it was. Problem it only tests around 20% which is not a lot of use. So I tested a #42 which is the same thing with a 6.3V heater. Its actually good.

I did find that running the # 42 for a few minutes did cause the emission to improve.

Are you a member of the HRSA?

No.