This little 1938 radio came to me in a small collection that were left in a basement for many years, then a loft space. Those conditions had quite a negative effect on the metalwork of the chassis but happily not insurmountable and the cabinet was in quite good condition to begin with.
The 808 is known as a ‘transportable’ as it was easily moved using it’s carry handle, but more impressively included a built in aerial. It’s construction is quite unusual, in that the chassis is a mixture of hardwood and steel and is a tight fit into the cabinet. The two aerial coils (frame aerial) for LW and MW are wound around the outside of the wooden chassis. Another unusual quirk of the design is that the electronics is spread over three chassis areas, left, right and centre-front.
The picture above those the set it it’s original condition. The weird yellow swollen blob in the top-right corner was a special block that contained electrolytic capacitors for the power supply. The out of place looking transformer centre bottom was a replacement speaker transformer connected in to take over the role of the original one centre top. It seems that this set has been subject to ‘cheap and quick’ repairs in the past.
I usually start with the power supply on a mains powered set. On this one, the transformer was in good condition and just needed new external wiring. The electrolytic capacitors needed replacing and there was also a smoothing choke (can be seen attached to the speaker on the right) This was blown and also needed replacing.
Usually all the wax capacitors are shot and need to replaced with new axial polyester caps. The RF section on the picture below was a bit tricky to do because it was made up with three separate tag boards in very close proximity to each other.
Overall, I was able to make a couple of general layout improvements. Firstly, because modern electrolytic capacitors are so much smaller that original, it was practical and safe to solder them directly to the underside of the rectifier tube. This had the advantage of freeing up space in the upper left corner of the chassis to secure the new (bigger) power supply smoothing choke.
Because the old blown choke could be removed from the right of the speaker, that freed up space to mount the replacement speaker transformer.
Overall I’m very happy with the performance of this set, the sound output level is very strong and it has very good tuning sensitivity and selectivity.
The replacement speaker transformer is mounted onto the speaker where the choke was. The power supply transformer has been rewired earthed and painted. A nice braided three core flex added. You can see the smoothing choke in the top right corner. The blue insulation tape was added to protect the frame aerial winding from damage during chassis refitting.
The video above captures it’s sound output