New Model #3363


Kenwood TK-790 Single Head

Added by Pavel Milanes almost 8 years ago. Updated over 3 years ago.

In Progress
Target version:
Start date:
Due date:
% Done:


Estimated time:
Equipment Loan Offered:
I read the instructions above:


I got a Kenwood TK-790 with a single head borrowed from a friend for a week or more, with a homebrew interface that has it's tricks... more on this later

I'm tainting it and found it use a single wire bus at TTL levels and the interface talks DIRECTLY to this "TRD" bus.

It has Three blocks of memory, corresponding (as per my assumptions) to the main three IC that connect to the bus:

  • The main CPU
  • The Head CPU
  • Other undetermined now.

I see a checksum on just one of the three blocks, I will check if it's a classic checksum, more on this later.



o.img (24.1 KB) o.img First image of the Sample TK-790 radio I have here. Pavel Milanes, 02/20/2016 02:21 PM (16.5 KB) Tom Hayward, 02/20/2016 07:58 PM

Related issues

Related to New Model #2835: Kenwood TK Commercial seriesClosed08/26/2015

Has duplicate New Model #2345: SGC SC-2020New02/23/2015

Has duplicate New Model #3307: Would like to pay to have models added to CHIRPFeedback02/10/2016

Actions #1

Updated by Pavel Milanes almost 8 years ago

  • Assignee set to Pavel Milanes
  • Chirp Version changed from 0.4.0 to daily
Actions #2

Updated by Pavel Milanes almost 8 years ago

  • File o.img o.img added
  • Status changed from New to In Progress
  • % Done changed from 0 to 10

Progress people !!!

I have now a working download/upload helper script, I have figured out the mem layout and Checksum. I will be now get busy creating the skeleton of the driver and starting to map the mem.

Attached is the first memory image

Happy weekend.

Actions #3

Updated by Mike Maynard almost 8 years ago

Awesome!! Keep me posted on this

I have not been able to get anywhere with the TK-780 but maybe the more you get going, I may be able to make more sense of it!

Actions #4

Updated by Pavel Milanes almost 8 years ago

The radio has 3 main block of memory that get read independently by different algorithms, for Chirps engine I will concatenate it as follows:

Low memory (Apparently Main CPU data & settings)
0x0000 to 0x4000
Mid memory (Unknown yet)
0x4000 to 0x4090
High memory (Apparently Head memory with channel data)
0x4090 to 0x6090

Data in the mem is at a glance, 73 I get back to work on it.

Actions #5

Updated by Tom Hayward almost 8 years ago

I started on the TK-790H a few years ago. I'm not sure how useful it will be, but here is my work-in-progress. I don't recall how much of this is complete vs copied from another driver and unmodified (for instance, I know I never tried an upload, so the upload code is probably wrong). Hopefully it will save you a little time.

Actions #6

Updated by Pavel Milanes almost 8 years ago

Interesting, I will review it a few minutes.

I'm giving the final touch to the set_channel now, and the download/upload is working well.

The channel management by it self is working fine, but I need so analyze more closely the other areas in which banks vs. channels are arranged, it's at a glance much similar to the TK-760G one.

I will end the set_channel and give a look to you code, I will call it a good night.

Thanks for sharing it.


Actions #7

Updated by Pavel Milanes almost 8 years ago

Just an update, I have completed the download/upload, channel management and bank management.

I have a few kirks to resolve with the offset=off and some banks layouts from real radios not working, this is interesting...

This radio has a bank limit and bank belongings section in the memmap, if you start with a clean program with the KPG44D software my driver works fine, but I have found that the former programming from the radio as it get borrowed to me is a kind of corrupted.

It has 9 channels in 3 banks, banks 1, 2 and 160, hum 160... this is weird...

When you looks to the banks limits you see that only 5 channels are covered and in the bank belongings area there are 9 channels; then the radio display the 5 correct channels in banks 1 & 2 where you expect and the other 4 channels are assigned to banks 160...

I have tried to replicate this from a clean KPG44D software layout and it has been impossible to end with a layout like the described (broken) one...

I think it's the result of mixing a radio body with other radio head, as this radio store data in this two places separately...

We are close... 73

Actions #8

Updated by Pavel Milanes almost 8 years ago

Ha !!!

The driver is capable of recognize the band segment of the radio (K 148-174, K2 136-156) automatically and will refuse to program a radio that is not in the same sub band.

Also I need users of this radios with the complex front (a lot of buttons and no front speaker) to contact me, I need an image of this exact model to compare and mod the driver as needed (if needed).

Actions #9

Updated by Pavel Milanes almost 8 years ago

Good news, with the Help of Tom Hayward we tested the two possible front heads for this radio, and I can tell that at a first look they are the same in the memory business.

That's a good news because I don't have to program separate functions to manage two kinds of front heads and that's saved time & efforts.

The first driver is almost done, I have to polish some issues and validate it against Chirp's test bed... I think that for the weekend we will have a patch for it on the "to release" queue.

This first driver will have only channel & banks management, no settings and no buttons; that will be in a second round.


Actions #10

Updated by Pavel Milanes almost 8 years ago

A pre-release version with full channel support and basic banks management is available for who wants to try it; if you like to try please click on my to see my email and drop me an email for driver + instructions.


Actions #11

Updated by Pavel Milanes almost 8 years ago

  • % Done changed from 10 to 90
Actions #12

Updated by Pavel Milanes about 7 years ago

Hi people, I'm dropping the development for this kind of radio.

I don't have access to any of this radios anymore, I have made a few attempts with the new fleet owner to borrow one of them again and no joy. The other in possession of a ham friend of mine was QRT (actually fried beyond repair) by a lightning stroke.

The partially working driver is available on request to a willing developer to finish the job. Tom Hayward was the leading person on this radios and I know he can follow the development if he have the spare time required.

73 Pavel CO7WT.

Actions #13

Updated by Tom Hayward about 7 years ago

What work is remaining? I thought it was complete.

By the way, I tried opening the Kenwood .dat file with this driver and a header offset provided by my FileWrapper patch. It mostly works! The only problem is that your upper memory block starts 16 bytes earlier than in the .dat.

Actions #14

Updated by Pavel Milanes about 7 years ago

Hi Tom,

You have in your inbox the latest version from my side (past eamils), fell free to update it with your patch and publish at your will, I can't get one of these on my hands any more to test/play/fix/etc (at least in the foreseeable future).

All the basic features are in the driver I sent you in the past, so after tour tweaks/test it can go public.

73 Pavel CO7WT.

Actions #15

Updated by Bernhard Hailer over 3 years ago

Keeping open until somebody can walk it the final mile.


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