Thanks for letting us know you are up again. And, thanks for the solution.
Chances are someone else will learn from your experience. Enjoy. Sent from my iPhone ...nr4c. bill > On Mar 4, 2017, at 2:54 PM, Irma Linas <[email protected]> wrote: > > Hello group, > > This might be usefull to all who own the Elecraft T-1 antenna tuner. Some > time ago I complained to this group and to the Elecraft support on problems > with T-1 had stopped tuning. The answer from the Elecraft Support was > quick and extremely usefull! Please find it below! Following their advise > I did check the resistance on diodes D1 and D2. It proved something was > wrong with the chain of the D1. The diode D1 though turned to be ok . The > faulty part was... the capacitor C11 wich was dead shorting the resistor R3 > to ground. I replaced the capacitor C11 with a new one ( not SMD by the > way, the " normal" one) and bingo! The problems gone , T-1 runs smoothly > and quickly . > Hope this info is usefull for the T-1 owners and you do have the schematic > diagram of the unit in order to better understand the whole thing. > > 73 de Linas LY2H > > <<<Elecraft Support: > > For the tuner to operate, it must see about a 0.5 to 3VDC FWD SWR sensor > level (depending on the power level) from diode D1's cathode, and a smaller > REFL sensor DC level (higher with more SWR) from D2's cathode - both when > you transmit with 1-10w or so of RF from your transmitter. If the 1N5711 > diodes are damaged, that won’t happen. > > > If the diodes are OK, there should be about 123K ohms (R3 + R5 or R4 + R6) > between each diode cathode and ground when tested with an ohmmeter, with > the positive lead on the banded end (cathode) and the negative lead to > ground. Bad diodes will have too much reverse leakage in the reverse > direction through the diodes and back through R1 or R2 to ground. > > Then, if your meter has a diode test function, there should be about 0.38 > to 0.40VDC of diode drop across the 1N5711 diodes, with the + lead to > anode, - lead to the cathode. 1N34A diodes will work in a pinch, but they > are not as good as the 1N5711 diodes which should be installed if you need > to get them.>>> > --------- > > <<<On Sunday, February 26, 2017 at 1:09:28 PM UTC-7, Linas Balsys wrote: > > Hello Support, >> >> My Elecrat T-1 mini-autotuner stopped working after some 10 years of >> flawless service... >> It started behaving erratically , it either does not react to the RF input >> , or if it does then never finds the tune ending up with the red LED on. >> It is not related with the antenna type, it is all t ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [email protected]
