I have had the opportunity to work on a TJ4A 4 Band HF Transceiver from a local ham. These are kits from a maker called Youkits and I am impressed with some details and not impressed with others. The problems with this rig began with a failing Push To Talk condition that stopped the keyer from making the rig TX. Later, the mic PTT failed as well and the rig would go into full transmit when turned on. As well the mic audio would then come out the speaker. After that it stopped turning on altogether with no power in any stage of the radio.