18-05-2022, 04:51 PM
I have been digging in the net. Sometimes the information you need is buried deep.
The site https://www.spartonradios.com/566.html shows the retro reproductions of the original 1936 Sparton Bluebird.
One is noted as "Thomson"
Now, the Radiomuseum shows the back of a Thomson Bluebird set.
https://www.radiomuseum.org/r/unknown_sp...d_rep.html
The back panel is missing from my set, but apart from it not having a tape player it is the same set. I will be able to recreate a back panel if I can sort the electronics.
Detection continued and I have found an applications sheet for SGS Thomson using the TDA1220 B chip.
https://pdf1.alldatasheet.com/datasheet-...A1220.html
I am assuming it is the same Thomson. Am I correct?
I have not compared that circuit to the set yet but there are many similarities. The sheet does not show a long wave aerial coil. But there is a double pole double touch slide switch for the 3 wavebands so it should be straightforward to graft in a new coil. Or one salvaged from an old ferrite aerial of which I have lots.
The IF transformers and the 2 transistors are at first glance the same. The AF amp chip is a known item.
So hopefully this is the circuit diagram, yippee!
Given a bit of time I may be able to make some progress.
The site https://www.spartonradios.com/566.html shows the retro reproductions of the original 1936 Sparton Bluebird.
One is noted as "Thomson"
Now, the Radiomuseum shows the back of a Thomson Bluebird set.
https://www.radiomuseum.org/r/unknown_sp...d_rep.html
The back panel is missing from my set, but apart from it not having a tape player it is the same set. I will be able to recreate a back panel if I can sort the electronics.
Detection continued and I have found an applications sheet for SGS Thomson using the TDA1220 B chip.
https://pdf1.alldatasheet.com/datasheet-...A1220.html
I am assuming it is the same Thomson. Am I correct?
I have not compared that circuit to the set yet but there are many similarities. The sheet does not show a long wave aerial coil. But there is a double pole double touch slide switch for the 3 wavebands so it should be straightforward to graft in a new coil. Or one salvaged from an old ferrite aerial of which I have lots.
The IF transformers and the 2 transistors are at first glance the same. The AF amp chip is a known item.
So hopefully this is the circuit diagram, yippee!
Given a bit of time I may be able to make some progress.
Boater Sam.
