I have an Elecraft T1 tuner that doesn’t seem to have any memory of its status: when starting a tuning cycle it doesn’t recall a previous tuning solution from memory, it starts from scratch and takes several seconds to get to what should be a known good LC configuration. Additionally it doesn’t toggle between inline and bypass, it only goes to bypass, the only way to re-engage the tuner is to attempt to go back inline (no green light and no relays clicking) and then start a new tuning cycle.
Did the EEPROM inside the PIC16F876A MCU go read only?
It’s possible that the write endurance for the EEPROM has been exceeded but it is the order of 1000000 cycles. i.e. many, many more write cycles than modern MLC flash on disk drives. That’s a lot of tune cycles!
Maybe your PIC has failed prematurely ? But ISTR you can still buy a programmed PIC from Elecraft for about $70US.
Here’s a slightly more serious comment from me, hi.
I’ve been using Elecraft T1 antenna tuners for a good 20 years. The first one was a kit version, and later I added a factory-built T1.
Both of my T1s have worked flawlessly to this day, without a single malfunction.
All the “functional problems of the T1” that I have heard or read about during this long period were caused by users: mostly contact problems due to loose solder joints/traces of the BNC sockets on the circuit board (e.g. caused by BNC adapters for thick/heavy coaxial cables) or contact problems in the 2 push button switches (e.g. caused by pressing too hard, especially for the long time press…).
Based on your description of symptoms, it’s quite possible that one of the two push button switches is defective and that there is a loose connection at the solder contacts of the BNC socket for the antenna/dummy load (e.g., which can lead to random/unsaveable tuning results).
In any case, it might be advisable to contact Elecraft support; they could guide you through a step-by-step troubleshooting process. Elecraft get-support
EDIT
If you’re not the first owner of this T1 and it’s not factory-built, then a mistake by the kit builder can’t be ruled out, meaning that this T1 never worked properly, as in this case:
No, it is indeed used, I don’t know if factory built or kit.
The malfunctioning is very peculiar, the buttons work, the tuning works, but the unit is stateless.
PWR + BYP = yellow led blinks, relay clicks and it goes to bypass; the same combo should blink green and go inline, it blinks yellow again, no relay clicking, still in bypass, but if I attempt a tuning cycle it performs it flawlessly, but it doesn’t recall the solution from memory.
I’ll try contacting Elecraft support as you suggested.
