Early Electronic Television
RCA TRK-5 Restoration
The Cabinet. (pictures) The cabinet is in good condition. It can be touched up. The safety glass in front of the picture tube has spots between the two layers of glass. A new one will have to be built. I have made a new safety glass by purchasing a piece of new glass the proper size, masking the screen area, and spray painting the glass the same color as the old one.
I have put the chassis back in the cabinet and installed the new safety glass and the CRT. The set works nicely now. The only thing missing is new pushbuttons for the radio. The plastic has decayed on the pushbuttons.
I found a source for new pusbuttons, and new ones have been made.
The Chassis. Here are pictures and technical information. The chassis will be cleaned with water and a mild detergent using soft brushes to get into small places. Then, all paper capacitors will be replaced with modern ones (see the procedure for this). Each electrolytic capacitor will be tested for leakage and capacity. If bad, new electrolytics will be installed inside the old ones. The high voltage (EHT) capacitor also had to be rebuilt.
The TV chassis in the set is identical to the TT-5. This chassis is in good condition, and is complete. The power transformer appears to be good. There is also a radio chassis for this set, which is also in good condition. The metal shield for the CRT and the CRT are both missing.
I have rebuilt the capacitors in the sweep section, and in the high voltage (EHT) and deflection circuits. I have also replaced the can electrolytic capacitors. Many of the paper capacitors have been replaced with modern ones. I am replacing them with ones inside some extra shells I have that look similar to the originals.
I found that many of the resistors in the high voltage (EHT) divider section were bad and have replaced them. After this, I have a good raster.
The tuner in this set had been changed substantially. Apparently, there was only one channel in the city where the set was used, since the tuning switch had been disabled. I rewired it back to the original layout.
I have not yet rebuilt the paper capacitors in the RF, IF and video sections. However, after connecting a signal, I have a good, solid picture. I also have sound at the output of the set.
When I receive a new stock of capacitors, I will finish rebuilding the remaining capacitors. I also found a number of bad tubes (valves). This is unusual - I generally only find one or so bad in a set.
I have a spare CRT, and have located a couple more for the other 5 inch sets. So, when the capacitor rebuilding is complete, the TV portion of this set will be done. I think the set will operate OK without the CRT shield as long as non-magnetic materials are kept away.
The restoration of the TV chassis is now complete, and the set displays a good quality, but dim (all the sets using 5BP4 picture tubes were dim) picture. The underside of the chassis looks closer to the original, that is, the capacitors look like 1940 vintage. However, the original RCA capacitors were plain cardboard cylinders with the values stamped on them.
After rebuilding the paper capacitors and replacing a bad resistor, the radio now works. The dial cord also had to be restrung. The restoration of the set is now complete.