Adding 18v to the Minitiouner, help!

[greg]

Hi all

Minitiouner v2

I have a buck converter to drop the 12v down to 5v to drive a relay (one of the Arduino ones).
I have a boost converter to increase the 12v to 18v for the LNB.
I have a relay (mentioned above).

The relay side of it:
+5v from buck converter to DC+ of relay coil
gnd to DC- of relay coil
IN1 (trigger) comes from where on the minitiouner?

+18v from boost converter to COM of relay
N/O goes to where on the minitiouner?

Basically, I need to know the 2 pins:
LNB vertical signal pin
LNB point to feed +18v

Studying the schematic and the FTS-4335 I believe that LNB_A1 (J4 pin 1) for Antenna A and LNB_A2 (J3 pin 1) for Antenna B are where the +18v should be injected to select vertical polarisation but I do not want to fry anything.

Which pin (or pins, there are 2 antenna ports) is the one the software turns on when you choose vertical polarisation?

Massive thanks for the help in advance

de M0ODZ

Greg - who is ---> this close <--- to completion

[radiogareth]

Short term.....unless you want to do Narrow band AND Wideband, just use the 13V that exists on the nim PCB via the tiny shorting links and twist the lnb 90 degrees.
Or since you are very nearly there, it's (from memory) either of the jumper pins nearest the edge of the PCB. You can check for continuity from the f connector centre pin. Be aware that it's via a tiny inductor in the Nim that goes open circuit if it ever sees a short.
Have you checked the Wikipedia article?
MiniTioune - BATC Wiki https://share.google/vdMrdvHIxbebmV0of and
SERIF.pdf https://share.google/y9J46bhgyH94Bofoi where you can see the jumpers.....wise to include a suitable current limiting resistor perhaps. There is an option to add a 'proper' PSU sub-board, part of the build for the later picotuner.
Gareth

[g0mjw]

Basically, I need to know the 2 pins:
LNB vertical signal pin
LNB point to feed +18v

There is no LNB voltage signal pin on the BATC minitiouner V2, it was all manually selected back then. The later minitioune software can drive an LNB bias board, but that's not included in the V2 which dates from 2017. It is included in the later Picotuner, which would have been a better place to start in 2026 for the additional cost of a new PCB and some parts but minus the high cost of the FTDI board. I assume you acquired this already built rather than built it recently. There is a pin from the FTDI module but I don't remember which, AC7 maybe. Check the instructions for the bias board.

There is a header, LNB A1 or LNB A2, where you can provide a supply. Normally these jumpers connect the 12V supply to the LNB via the tuner module and coax. Be carful not to short out the 18v as it will probably fry the RFC in the tuner module. If you did get it second hand, it would not be a surprise to find that has already happened. Better to use an external bias-T. I don't know what the 5V relay is for so can't comment on that.

https://wiki.batc.org.uk/MiniTiouner_hardware_Version_2
https://shop.technofix.uk/satellite-bia ... for-qo-100
https://wiki.batc.org.uk/Serit_LNB_DC_s ... iniTiouner

Mike

[greg]

Hi both

Many thanks for the answers.

I do have the picotuner as well as the original ftdi module.