I'm looking for a service manual in PDF preferably for a Bendix King KX99. I have a schematic but nothing showing board layout and parts locations. I have an old KX99 here I'm trying to get back into proper working order. Thanks.
They seem to be available on some "unsafe" Kindle Reader web sites but they require registration and your credit card details which I'm not prepared to give. I made my KX99 out the broken parts of three or four of them - the ground crew hosties tend to check if gravity is still working by bouncing them down the aircraft steps or swinging them round by the rubber duckie. I haven't had it apart for a while so memory is a bit dim but I recall that there are quite a few push-on connectors inside - you could try re-seating them for a start. Mine still works well and also good on an external antenna - I permanently wired the TX lock button so that inquisitive little fingers didn't try talking to that 74 that just went overhead.....
This one was found with a pile of junk on a tarp at the Dayton hamfest a few years ago for like $1. The screws were missing from the back and the back was off and sitting to the side. It has some wear but not too bad considering. It had rained so there was a bit of corrosion on the parts on the back PC board. I messed with it and assumed it didn't work but recently checked it out again and found I was wrong. It was just a bit low in sensitivity. I put it on the test set and readjusted the slugs in the receiver which perked it up quite a bit. It also seemed someone had ramped up the output power as far as possible so I backed that down to normal level. I put some new screws in the back. So far it seems to work fairly well. It was also off freq by about 5 kHz but I got it back close as I could (about .5 k off) until I ran out of varicap adjustment.
I was hoping to find the manual to make sure what tuning slugs were what but I guess now that it's pretty much working normally it's not a big deal.
I wish they would have made their other radios similar to this. The case, buttons, and internal connections are of much better design.
Yes, the operator's handbook is easy to find but the service manual.....
When we were repairing the KX99's before the trunking network came into use, my apprentice thought he would give the transmitter of one he repaired a tune-up. Nominally only 1.5watts he squeezed more than 3 watts out of it. Funnily enough, he never got any replies to his test calls. When I looked at his method, he had just used a power meter and a dummy load to tune into. We hooked up the spectrum analyser to an attenuator and then to the load and - surprise - there were spikes of power all over the place but very little on the required frequency! Gave it another tune-up to maximise the on-frequency spike and it worked much better - but still just over a 1.5watts!