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Wanted info on Mobat antenna tuner

Posted: Sun Dec 26, 2010 5:08 pm
by JMINN
I am looking for instructions for operating the motorola F2265A hf-ssb antenna tuner. Any help will be appreciated.
Thanks

Joe

KC5DPV

Re: Wanted info on Mobat antenna tuner

Posted: Mon Dec 27, 2010 7:14 pm
by jnglmassiv
Those are intended to be used with the Mobat/Motorola Micom 2 and 3 HF radios. From my ATA-125 (WIMA) manual:
Tuning Unit operates in the following modes:
- Initial mode set up (BY-PASS mode)
- Matching loop tuning by algorithm
- Tuning from the memory on pre-programmed frequencies

At the Tuning Unit case there is [sic] RF connector that is used to supply up to 125W RF power from transceiver output to the Tuning Unit input with the +12V power voltage.

Tuning mode starts up once power supply voltage is applied to RF connector.
The Controller goes from sleep mode and waiting for 3-6W RF signal during 200ms.
If RF signals does not comre during 200ms then the controller will set up tuning elements to initial state (BY-PASS mode) and turn to sleep mode.
If RF signal comes during 200ms then the controller measures RF signal frequency, sets up tuning elements from nonvolatile memory and checks VSWR.
It goes on for some time describing internal operation if the tuned frequency is not in memory if if the VSWR is greater than 2. The manual production quality and translation editing are a bit rough. Suffice to say, the radio will need to provide power and a timed 3-6W tuning signal. The only connection from the radio to the tuner is the coax which carries tuner power and control as well as RF power to the antenna. You do need to configure the radio to enable the tuner option under the ACC menu. I haven't used the F2265A but the other tuners I have are nice quality gear.

Re: Wanted info on Mobat antenna tuner

Posted: Tue Dec 28, 2010 12:59 pm
by JMINN
Thanks for the information. Do you have a circuit for it? One of the parallel chip caps (inductors?) has a hole chipped out of it. I would also like to modify it for a seperate 12v supply.

Joe