17-03-2026, 04:45 AM
Hello all It has been a while since I was last able to get back to my work bench. Health issues slow me down a little but my doctor tells me that I am in good condition, (for my age!)
Anyway, back onto topic. I recently came across a basket case of a radio, and because it was a model I've never seen before, I put my brain into neutral and bought it.
The radio is from about 1963, and is a five valve, live-chassis type, compact mantle. It has a four position rotary switch giving
A paper schematic label was glued to the inside of the cabinet, so I figured that would be enough to fix it.
Apart from one missing knob and and a cabinet that would make a cabinet maker cry, I began to fix the radio knowing that I would give it away after fixing it.
I disassembled the set as much as I could, cleaned off the chassis and had a good look at what was under all the dust. First the mains fuse did not look right. Hmm. 25A fuse? Seemed a little high. I replaced it with something around a quarter amp. Next I replaced all the paper caps. I changed the electro in the output valve's cathode, and re-formed the main filter electro at a low mains input for a few hours.
The power supply is a little odd, (read dangerous) in this set. The Aerial, the aerial's earth end, the pick-up, and the radio chassis, are all isolated from the mains by some wonderful sixty year old paper capacitors. what could possibly do wrong? Apart from the obvious, if the active side of the mains is the side being the, radio's earth, (a bus-bar from tag to tag underneath the chassis), the tuning gang and the dial drum will be live. It is connected to the-bus bar.
In this case of my radio, the insulating grommets had turned into a white goo and flowed away decades ago. Now every piece of the chassis would become live. Hmm. thinking of that 25A fuse again.
Long story short, it's now working.
Because the schematic was so poor, I used it in conjunction with the circuits for National EE-345J and GU-362.
If I can, I will try to attach a photo of what I am working on now.Let' see who can recognise it.
Anyway, back onto topic. I recently came across a basket case of a radio, and because it was a model I've never seen before, I put my brain into neutral and bought it.
The radio is from about 1963, and is a five valve, live-chassis type, compact mantle. It has a four position rotary switch giving
- pick -up
- broadcast band
- SW-1
- SW-2.
A paper schematic label was glued to the inside of the cabinet, so I figured that would be enough to fix it.
Apart from one missing knob and and a cabinet that would make a cabinet maker cry, I began to fix the radio knowing that I would give it away after fixing it.
I disassembled the set as much as I could, cleaned off the chassis and had a good look at what was under all the dust. First the mains fuse did not look right. Hmm. 25A fuse? Seemed a little high. I replaced it with something around a quarter amp. Next I replaced all the paper caps. I changed the electro in the output valve's cathode, and re-formed the main filter electro at a low mains input for a few hours.
The power supply is a little odd, (read dangerous) in this set. The Aerial, the aerial's earth end, the pick-up, and the radio chassis, are all isolated from the mains by some wonderful sixty year old paper capacitors. what could possibly do wrong? Apart from the obvious, if the active side of the mains is the side being the, radio's earth, (a bus-bar from tag to tag underneath the chassis), the tuning gang and the dial drum will be live. It is connected to the-bus bar.
In this case of my radio, the insulating grommets had turned into a white goo and flowed away decades ago. Now every piece of the chassis would become live. Hmm. thinking of that 25A fuse again.
Long story short, it's now working.
Because the schematic was so poor, I used it in conjunction with the circuits for National EE-345J and GU-362.
If I can, I will try to attach a photo of what I am working on now.Let' see who can recognise it.
