Vintage Harman Kardon 430 Twin Powered AM/FM Stereo Receiver

Description: For your consideration is a Harman Kardon 430 Twin Powered AM/FM Stereo Receiver. Manufactured around 1976, the 430 is a well-built receiver that incorporates dual power supplies, one for the left and one for the right channel. This provides better channel separation and a dynamic, full sound that's very impressive. After listening to this reconditioned receiver for several evenings, my wife and I agree it sounds amazing. I recently purchased this H/K 430 on eBay. When I received it, I immediately realized this 430 receiver was going to require a lot of work. Someone had already replaced all the transistors and capacitors on the main amp board. Unfortunately, they left the solder side of the board a mess. They also used NTE transistors, which are frowned upon by many techs, including myself. Two of the replaced capacitors were a lower value than original, not good. I had a spare original 430 main amp board, so I decided to rebuild that one. I installed new differential and voltage multiplier transistors. All others, including the output transistors, were tested and are good. All electrolytic capacitors were replaced. Both idle bias adjustment pots were replaced. All diodes were checked and are good. All emitter resistors and numerous other resistors were checked and tested good. I installed the reconditioned amp board in the receiver and began troubleshooting other issues. Turns out I had no power to the tuner or pre-amp boards. A bad 8 ohm resistor in the power feed was found to be the problem. I replaced the resistor, and now the pre-amp and tuner board were receiving power. I set the amp idle bias to service manual spec of 25mv on both channels and proceeded to test the tuner and inputs. The tuner was now working, but not properly. I hooked up my test equipment, made a few adjustments, and FM and FM stereo now work as they should. Very good sensitivity and excellent separation and sound stage on FM stereo. AM seems to work, but was also picking up what sounded like someone on a citizens band radio on 3 or 4 frequencies across the AM band. The signal was strong and garbled. I live in a rural area, and AM reception here is terrible, so while it seems to work, it may not be perfect. The phono (turntable) inputs were tested and found to be noisy. I replaced all the transistors and electrolytic capacitors on the phono equalization board. The output coupling capacitors were upgraded to WIMA metal film. The noise is gone, and the phono input sounds great. Aux and tape monitor inputs work and sound fine. Both tape outputs work as well. All functions were tested (loudness, stereo/mono, high and low filters, FM muting), and work as they should. The controls operate without noise and static. Both A and B speaker outputs provide warm, powerful sound. The bass is impressive, mids and highs are clear and crisp. Stereo separation and imaging are excellent. All new LED lamps installed in this 430. All controls cleaned and lubricated with Deoxit. Cosmetically, this receiver is no beauty queen, but it still presents well, and the front of the faceplate and the knobs cleaned up nice. The top of the faceplate had some numbers engraved into it. I wet sanded, then compounded and polished the top edge, and although the engraving is still barely present, it is quite difficult to see except in bright light. Please see the pictures. The top cover shows some wear and fading, but no damage. There are scuffs, scratches, and dings from normal use and handling. As I noted, it won't win any beauty awards, but it's not an ugly duckling either. The pictures tell the story. The sound, on the other hand, is very impressive. Shipping will be via FedEx Ground or Home Delivery within 3 business days of cleared payment. Insurance is included and a tracking number will be provided. Any questions please send me an eBay message and I'll promptly respond. Thanks for looking!

Price: 349.99 USD

Location: Brookneal, Virginia

End Time: 2024-11-17T01:41:56.000Z

Shipping Cost: 0 USD