# CAT Operation on a Kenwood TS-440S
**URL:** https://forum.digirig.net/t/cat-operation-on-a-kenwood-ts-440s/10438
**Category:** Uncategorized
**Tags:** kenwood-ts-440s, troubleshoot-serial
**Created:** [April 7, 2026, 12:01pm UTC](https://forum.digirig.net/t/cat-operation-on-a-kenwood-ts-440s/10438 "2026-04-07T12:01:42Z")
**Posts on this page:** 9
**Page:** 1
### Author:  [@Hcop1026](https://forum.digirig.net/u/Hcop1026)
#### Post date: [April 7, 2026, 12:01pm UTC](https://forum.digirig.net/t/cat-operation-on-a-kenwood-ts-440s/10438/1 "2026-04-07T12:01:42Z")
How can you tell if the two IC’s for CAT operation on the above radio are installed or not w/o opening up the radio??? Thanks
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### Author:  [@K0TX](https://forum.digirig.net/u/K0TX)
#### Post date: [April 7, 2026, 4:27pm UTC](https://forum.digirig.net/t/cat-operation-on-a-kenwood-ts-440s/10438/2 "2026-04-07T16:27:27Z")
The functional test would be one option, but if this is the first setup the chances are good that the test will fail for some other reason even with ICs installed because there are many variables.
The radio is between 30 and 40 years old. You will not be losing warranty by peeking under the hood:
[Adventures in Ham Radio: Installing an IC-10 kit into a Kenwood TS-440S/AT HF Radio](https://hamprojects.blogspot.com/2012/08/installing-ic-10-kit-into-kenwood-ts.html)
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### Author:  [@Hcop1026](https://forum.digirig.net/u/Hcop1026)
#### Post date: [April 7, 2026, 5:00pm UTC](https://forum.digirig.net/t/cat-operation-on-a-kenwood-ts-440s/10438/3 "2026-04-07T17:00:29Z")
That’s for sure ! I spent enough on it that I don’t want to cause more damage, lol
Thanks
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### Author:  [@Hcop1026](https://forum.digirig.net/u/Hcop1026)
#### Post date: [April 11, 2026, 8:22pm UTC](https://forum.digirig.net/t/cat-operation-on-a-kenwood-ts-440s/10438/4 "2026-04-11T20:22:25Z")
How can I transmit on FT8 without the cat control? Thanks
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### Author:  [@webmonkey](https://forum.digirig.net/u/webmonkey)
#### Post date: [April 12, 2026, 7:43pm UTC](https://forum.digirig.net/t/cat-operation-on-a-kenwood-ts-440s/10438/5 "2026-04-12T19:43:22Z")
in wsjtx, select rig control: NONE
then in ptt, select RTS and the appropriate comport.
good luck
🙂
kb0wlf
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### Author:  [@Hcop1026](https://forum.digirig.net/u/Hcop1026)
#### Post date: [April 12, 2026, 9:31pm UTC](https://forum.digirig.net/t/cat-operation-on-a-kenwood-ts-440s/10438/6 "2026-04-12T21:31:21Z")
Done that, no good but thanks
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### Author:  [@webmonkey](https://forum.digirig.net/u/webmonkey)
#### Post date: [April 12, 2026, 10:41pm UTC](https://forum.digirig.net/t/cat-operation-on-a-kenwood-ts-440s/10438/7 "2026-04-12T22:41:24Z")
what cable set are you using with the ts-440s digirig mobile setup?
using RTS for ptt is handled through through the audio+ptt cable of the digirig, not the serial/cat/ci-v/remote control cable.
are you connecting to the mic jack or the rear acc jack for audio+ptt ?
my IC-736 and IC-821h rigs all use RTS for PTT even though they have CI-V control.
they don’t support PTT via CAT/CI-V so i must use RTS.
they all key up fine with the digirig mobile
🙂
good luck
kb0wlf
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### Author:  [@Hcop1026](https://forum.digirig.net/u/Hcop1026)
#### Post date: [April 13, 2026, 10:41am UTC](https://forum.digirig.net/t/cat-operation-on-a-kenwood-ts-440s/10438/8 "2026-04-13T10:41:41Z")
Gm, I have the Digirig mobile, their cable set into usb on PC, two coiled connectors plugged into the rear accessory jacks of the 440S…I am set to RTS and receiving is fine, not able to transmit at all…Thanks.
WD9IWC
Someone replied to your post.
>  | [webmonkey](https://forum.digirig.net/u/webmonkey)
> April 12 |
>
> - | - |
what cable set are you using with the ts-440s digirig mobile setup?
using RTS for ptt is handled through through the audio+ptt cable of the digirig, not the serial/cat/ci-v/remote control cable.
are you connecting to the mic jack or the rear acc jack for audio+ptt ?
my IC-736 and IC-821h rigs all use RTS for PTT even though they have CI-V control.
they don’t support PTT via CAT/CI-V so i must use RTS.
they all key up fine with the digirig mobile
good luck
kb0wlf
---
### Author:  [@webmonkey](https://forum.digirig.net/u/webmonkey)
#### Post date: [April 13, 2026, 1:29pm UTC](https://forum.digirig.net/t/cat-operation-on-a-kenwood-ts-440s/10438/9 "2026-04-13T13:29:58Z")
ok, unplug the audio+ptt cable from from the digirig. keep the other end plugged into the radio.
short the sleeve and ring2 connectors of that cable and see if your radio switches into transmit.
(sleeve is the connection closest to the cable and farthest from the tip. ring2 is next to the sleeve)
good luck
🙂
kb0wlf