PHILCO 37-60

This radio was a real challenge. The owner wanted the radio fixed, but also wanted the electromagnetic speaker replaced with a PM type. The speaker itself was heavily damaged and the radio appeared to be water soaked. (The owner said it was not). See Figure 1.

The Electrolytics had already, many moons ago, been replaced with large under chassis caps. See Figure 2. The line cord was shot. All the remaining capacitors looked to be 65+ years of age - little time bombs waiting to go off. The power transformer appeared to be ok as did the rotary switch for band changes.

Ultimately two tubes had to be replaced - a 6Q7 and a 6F6.

The radio was repaired in several steps.

Step one was redesigning the power supply so that the radio did not rely on the speaker field coil for filtration. This involved substituting a 1.2K ohm 25 watt resistor in place of the choke coil.

The only place to mount this rather large resistor was on the surface of the chassis top, because of space limitations as well as heat dissipation. See Figure 3.

Given this placement, two of the three new Electrolytics were also placed above the chassis and connected to the terminal strip used for the 25 watt resistor. See figure 4.

Also, a new rotary reproduction frequency dial was ordered and placed on the radio. See Figure 5.

A new power cord was installed on the radio at this time.

A new audio transformer (Figure 6) was installed on top of the chassis to work with the new 8" 8ohm speaker (figure 7) that was ordered for this radio.

For convenience sake, new speaker terminals as well as, a new antenna terminal were placed on the back lip of the radio. See Figure 6.

All the Electrolytics as well as, the paper capacitors were replaced in the radio. See Figure 8.

Finally, all controls were treated with DEOXIT - Frequency alignment was checked. The radio proved to be very sensitive without any external antenna.

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