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IC-7300 expansion board

 

Ordered the overpriced PCB from EBay which came without any info on a BOM and very vague schematic. It needs two transistors that are unidentified. If any one has built one of these and got it working, I would be grateful for some advise. Thanks?
 

Hi.
Most likely, use Google translater
http://www.cqham.ru/forum/showthread.php?40049-%D1%F2%EE%F0%EE%ED%ED%E8%E5-%EC%EE%E4%E8%F4%E8%EA%E0%F6%E8%E8-%E0%E2%F2%EE%F2%FE%ED%E5%F0%E0-ATU-100-by-N7DDC-%E8-%EA%EE%ED%F1%F2%F0%F3%EA%F6%E8%E8-%ED%E0-%E5%E3%EE-%E1%E0%E7%E5&p=1719801&viewfull=1#post1719801
 
Edited

It looks like a useful thing, and I understand that it's supposed to link the IC-7300 to the ATU-100 so that you can use the "tuner" button on the transceiver.
But the schematics for that expansion board are kind of confusing to me. Does anyone know how to wire it correctly?


73, ²Ñ²¹³Ù¨§Âá OK2MTB


Expansion Board Adapter Board For ICOM IC-7300? ATU-100? Automatic Antenna Tuner by N7DDC 7x7 https://a.aliexpress.com/_mq68kly
 

²Ñ²¹³Ù¨§Âá,

Don't have an answer for your question, however I use the "Click2Tune" kit from SOTA Beams with an ATU-100 and it works well.

The schematic is available online, it is a simple circuit and has the advantage that it will also work with any other tuner.

Regards,

Matt

On Thu, Dec 15, 2022, at 15:54, ²Ñ²¹³Ù¨§Âá OK2MTB wrote:
It looks like a useful thing, and I understand that it's supposed to link the IC-7300 to the ATU-100 so that you can use the "tuner" button on the transceiver.
But the schematics for that expansion board are kind of confusing to me. Does anyone know how to wire it correctly?


73, ²Ñ²¹³Ù¨§Âá OK2MTB

 
Edited

²Ñ²¹³Ù¨§Âá

I haven't actually done this, but looking at the schematics, 4 of the connection points to the interface board are small pads on the rear of the ATU-100 board.

Two are labelled 'A6 & A7'? the other two are not labelled.?? But if you check with an ohm meter, the next pad on, adjacent to A7 pad is Pin-22 on the Atmega and the last pin is Pin-23 on Atmega.
Thus Pin 22 is the B1-Auto on the interface and Pin 23 pad is B2-Bypass on the interface.

ie the pads are:
  • A6
  • A7
  • Pin22
  • Pin23

The GND and +5V points can be connected to the 5v regulator device, a TO-92 device. Check a data sheet for correct pin-out of the 78L05.

It would appear you need two additional diodes, D4,5 to be added to X2, (the existing ATU-100 DC input connector) along with a suitable female connector (a DIN-5 it would appear) to connector the IC-7300 via a cable from the male DIN-5.? $X appears to be an additonal 2.5mm (?) socket for external ATU-100 power if required.

You should verify these connection details I have given, before wiring it up.

Glenn
 

¿ªÔÆÌåÓý

Hi Chaps,
In case it is a help...
This is what I did with my icom 7200
Tune on the atu button side works as does tune button on the 7000 and 7200.
best
Ian VK5IS



On 4/01/2023 11:15, Glenn wrote:

²Ñ²¹³Ù¨§Âá

I haven't actually done this, but looking at the schematics, 4 of the connection points to the interface board are small pads on the rear of the ATU-100 board.

Two are labelled 'A6 & A7'? the other two are not labelled.?? But if you check with an ohm meter, the next pad on, adjacent to A7 pad is Pin-22 on the Atmega and the last pin is Pin-23 on Atmega.
Thus Pin 22 is the B1-Auto on the interface and Pin 23 pad is B2-Bypass on the interface.

ie the pads are:
  • A6
  • A7
  • Pin22
  • Pin23

The GND and +5V points can be connected to the 5v regulator device, a TO-92 device. Check a data sheet for correct pin-out of the 78L05.

It would appear you need two additional diodes, D4,5 to be added to X2, along with a suitable female connector (a DIN-5 it would appear) to connector the IC-7300 via a cable from the male DIN-5.? $X appears to be an additonal 2.5mm (?) socket for external ATU-100 power if required.

You should verify these connection details I have given, before wiring it up.

Glenn

 

The Expansion Board is unnecessarily complicated.? To operate the ATU-100 from Icom transceivers with the 4 pin Molex TUNER port,?
Simply connect 560 ohm resistors to the A6 via and B connector on the ATU-100 board and connect to pin 2 (_KEY) and pin 1 (_START) respectfully on the Icom TUNER port (plus +12V and ground).
The resistors protect the microcontroller from accidental connection to +12V or ground.? I have made this modification to a couple of ATU-100 boards and it works fine with several Icom transceivers.?
The ATU-100 behave like the Icom and LDG autotuners.?
Refer to page 6 of??
to see how _START and _KEY operate.?

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