RFT EKD-100 Service Manual
Going through my pile of HAM stuff, I’ve stumbled upon a hard-copy of the Service Manual of the RFT EKD-100 commercial MF-HF receiver. It was sent by unknown employee at Koepenick /the former factory of RFT/ in Germany, by the request of my friend LZ3NY Mitko. Somehow he was able to find an email contact…
Replacement of RL1 LZN4 Omron relay in TS-830S
Here’s yet another approach to solving an issues with the hard to find LZN4 Omron relay on the AVR Board in Kenwood TS-830S transceiver /part # S51-4401-05/. It’s a 4PDT relay with 12VDC coil, switching various voltages. After few decades and frequent transmit/receive actions, the contacts of this relay become intermittent, resulting in poor receive…
CW Cable For Hybrid Transceivers Using Solid State Relay
Well, the title says it all. The cable is built around the NEC’s PS7205B-1A SSR, which is with GaAs LED input and optically-coupled dual MOSFET output. The schematic is simple. The only caution is that the C2 — the capacitor at KEYING side, must be rated at 100V. This is because in TS-830S for example,…
A Cheap VHF UHF Dipole
Here’s my variation on dual band dipole from drawings found on the web. Mine is made from stainless welding wire with 1.5mm diameter. The fasteners are M4 A2 /stainless/ machine screws, nuts, and washers. After adjustments, the total length for the 2-meter band is approx. 960mm in total. The spacing between two halves is about…
Kenwood TS-830S shaft couplings replacement
Here’s my approach to problem with the cracked plastic shaft couplings in the Kenwood TS-830S hybrid transceiver. As you may already know, after 30+ years, these couplings tend to crack and almost no adjustments could be made to the TS-830S. One of the main reasons for the cracking of these couplings is overtightening the set…
Kenwood TS-830S PA Board
PCB of the PA Board of the TS-830S