Icom IC-720A (IC 720 A IC720A) transceiver mods reviews software and diagrams

   
 
ham | what is new | links
 Welcome to Www.Hampedia.net  submit to reddit
14 November 2019, 18:48 UTC 


SDR


ELAD
SDRplay

Transceivers


Kenwood
Midland
Yaesu
Alinco
Icom
Other

Antennas


M2
Par
Gap
Sirio
Araki
Maco
Nil-Jon
Maldol
Comet
Hustler
Nagoya
Watson
Hy-Gain
Dressler
Cue Dee
Solarcon
Diamond
Cushcraft
Quicksilver
Moonraker

Power supplies


Powerbox
Kenwood
Diamond
Samlex
Mascot
Daiwa
Yaesu
Alinco
Icom
H&H

Rotators


M2
CDE
Yaesu
Create
Kenpro

Antenna tuners


MFJ
LDG
SGC
Icom
Yaesu
Mizuho
Dentron
Kenwood
Sommerkamp
Barker & Williamson

Repeaters


GME
Icom
Zodiac
Kenwood

Transverters


Microwave Modules
Tokyo Hy-Power
SSB Electronics
Tecnostudi
Kenwood
Yaesu
Minix

Meters


Diamond
Comet
Bird
MFJ

Ham resources


Propagation:
  Sporadic E skip (Es)
  Backscatter
  Tropo
  Meteor Scatter (MS)
  F2 Skip
  Aurora
  Trans-equatorial scatter (TE)
  Lightning scatter (LS)

Icom IC-720A (IC 720 A IC720A)
IC-720A
Programming interface schematics for Icom:
Programming software for Icom IC-720A (IC 720 A IC720A) :
PDF User Manual for Icom IC-720A (IC 720 A IC720A) :Icom IC-720A Instruction Manual
PDF Adjusments Procedures Manual with schematics for Icom IC-720A (IC 720 A IC720A) :
Schematics for Icom IC-720A (IC 720 A IC720A) :

Mods for Icom IC-720A (IC 720 A IC720A) :
    Icom IC-720A (IC 720 A IC720A) Rotaryswitch mod
    Icom IC-720A (IC 720 A IC720A) extended xmit
    Icom IC-720A (IC 720 A IC720A) Modifying IC-720A to get rid of rotary relay
    Icom IC-720A (IC 720 A IC720A) Amtor mods

Icom IC-720A (IC 720 A IC720A) technical specifications :  Icom IC-720A (IC 720 A IC720A) technical specifications



Icom IC-720A (IC 720 A IC720A) Amtor mods

I present here again the mods for amtor operation for the Icom IC-720A transceiver.
On my Icom IC-720A i did the first set of mods and now my Icom IC-720A works well in amtor and packet !

I hope that this infos are useful for someone!

Mods for the Icom IC-720A:
There are 4 sets of mods. Some duplication will be obvious.

Main board:
Change C40 C42 C43 C54 to 0.1 uF
Change C69 TO 0.01uF.

I.F. Board:
C87 may be 33uF, but shown as 0.0047uF, which is on print side.
Change C87 to 2.2uF, leave 0.0047 on print side.

R.F. Board:
Remove C169 C127. Change C165 to 0.47uF.

Noise blanker update. (check if done)
Change C116 to 10uF
Change C171 to 0.01uF

If in difficulties call england 2273 63859


Delete C40 and C43 on main unit

Change C42 and C43 (10uF and 2.2uF) to 1uF.

Disable A.F.Muting- link short-C69.

Delete cap. CT14 at pin 6 of IC3 on I.F. Unit.

Rearrange the R9V to TR Q22 on I.F. Unit so that it is connected to unswitched "9volts supply.

Do a similar mod. To the "9 volt supply to the A.F. unit to overcome surge pulse.

Connections to acc. Jack on the back of the tansceiver:

Pin 3 Keyline (note that 200 mA current capability is required so a dil relay may give problems)
Pin 4 af to convertor
Pin 9 FSK input TTL level
Pin 8 ground

On main board:
Remove C40/42/43/54 and replace by 0.1 uF
Replace C69 by 10 nF

On RF board:
Remove C169 and 127 and replace C165 by 0.68 uF when desired the relay to control an external linear amp can be disconnected to reduce the clicking noises

CB Equipment


President
Midland
Uniden
Zodiac

 Power amplifiers


Beko
Icom
Alinco
Drake
Yaesu
Daiwa
Collins
Kenwood
DanAmps
Ameritron
Autophon
Eto/Alpha
Command Technologies
E.F.Johnson
Dentron Radio Co.

FRS/GMRS


Bell
GPX
ENC
Tekk
Icom
Sony
Alinco
Drake
Cobra
Maxon
Vertex
Conair
Uniden
Jenson
Ranger
Midland
Whistler
Magnum
Unwired
Coleman
Motorola
Audiovox
Memorex
Columbia
Samsung
Standard
Kenwood
Cherokee
Panasonic
Freetalker
Vtech Vtalk
RadioShack
Fanon Courier
Sharper Image
General Electric
Oregon Scientific

PMR446


Sommerkamp
FreeQuency
Goodmans
Kenwood
Lafayette
President
Binatone
Motorola
Multicom
Albrecht
Maycom
Topcom
Xtreme
Ondico
Telcom
Maxon
Vertex
Zodiac
Yaesu
Cobra
Alinco
Icom
Alan
ITT