TenTec Radio Kit - Model 1054 Update #3

My longtime readers will remember I built a TenTec Model 1054 regenerative shortwave receiver kit a while back. At the time I posted to this blog about the apparent bad customer service I received from TenTec when complaining about the erratic regeneration control. Just week, there has been another development.

This past week I have been working feverishly to get all my ham and shortwave equipment up and running. After an exhaustive and *fruitless* search online, trying to find any information I could on the TenTec 1054's regeneration control issue, I decided to try once more to contact TenTec's customer service people. TenTec apparently has NO PHONE number to reach them at; apparetly one must email them as I had before. And so I did.

The following day I got an email back from one of their service technicians stating that my original email had gone into his email "spam folder". He also stated, contrary to the instruction manual, that the regeneration will start 1/4 of the way from one end of the potentiometer's travel, that regeneration will start rather suddenly, and that from my description the radio seemed to be working correctly. ANOTHER tech later wrote me and said that he thought there was a defect in either one of the two FET transistors in the regeneration circuit or that the regeneration threshold adjustment trim potentiometer was bad. He offered to send me new parts free of charge if I sent him my address. I did just so; I'll see what happens.

If they do not end up sending me the parts (I'm NOT holding my breath, under the circumstances), after studying the schematic at some length I have some ideas as to how I can modify the circuit to work better.

All this said, I still have the issue of what to do about the housing, since the box TenTec sent me is basically unusable. As mentioned in my original post I intend to do some circuit modifications such as adding a dual 9-volt regulator circuit that can be fed from an external 12 volt battery, and possibly adding a band spread control for better selectivity in crowded bands. I want to build my own improved audio section based on a decent audio chip. I would also include an active filter for CW reception and a limiter to prevent hearing damage from loud noises. Regarding the dual 9-volt regulator, the circuit currently uses separate batteries for the regenerative receiver itself and the audio section. This is no doubt to eliminate any issues from feedback and oscillation between the radio part and the audio section. But for my purposes I need the whole thing run from one 12 volt battery.

Here are the links to my prior posts regarding the TenTec Moel 1054 radio:

http://inkarlslab.blogspot.com/2011/04/ten-tec-short-wave-receiver.html

http://inkarlslab.blogspot.com/2011/05/ten-tec-model-1054-shortwave-radio.html