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Drake Pages. TR4 transceiver full restoration projectFeb 2004, the Drake TR4 Project. Not an easy one this, although this poor TR4 does actually function on receive, it looks as if its been left in the damp for years. Its important to test with a correct Powers Supply that includes the -ve bias as its used for the AGC and VOX circuits. On 80m the RX performance seems OK without any alignment.
The front panel is badly pitted and the chassis has signs of corrosion. If I can get a new front panel, it could be made presentable.. also needs three 6JB6 output tubes... so it wont be cheap to get going. Oh - and these pictures were taken after I spent some time cleaning it!!!!
The case screws can be repainted with Hammerite as well - I pushed them all into foam plastic and the sprayed the screw heads. New screws (6-32 1/4 inch) are available in the UK on this link from skycraft and cost around £11 for 100 - again spray black. This rebuild will create the worlds first TR4 with a TR3 front panel, but the end result will be a very clean radio. A full and carefull re-alignment will then follow and we will see how far we get - check back to see how it goes . As ever its the mechanical problems that cause a lot of problems in older equipment - the receive protection 6V bulb caused the RX to die as it warmed up, I found this by accident checking the antenna relay, the bulb connections were corroded. All the potentiometers needed either replacing or cleaning... the most frightening was the TX gain control which also controls the amount of drive in tune up. This was putting max drive into the TX before I cleaned it and had the finals drawing over 0.5A. even when it was set to zero.!! Despite all this work the majority of the TR4's electronics were in good order, and I have not yet changed any tubes (except the missing finals), I did not expect this and prepared for a lot more work.  April 17th 2004, this is how it ended up, US replacement parts and repainted case have transformed the transceiver!. GE output tubes fitted. I have kept the TR3 look although inside its still a 1965 TR4. Works well too, receiver is excellent after alignment and TX is full power on the lower bands. I get good reports on 80m although the ALC seems to peg the power back more than my TR4CW when used on SSB |
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