New expansion - uPD2824 chassis

[cb4ever104]

Hopefully you'll lots of use out of that radio after putting in all that effort to mod it...

Probably not Sue . It'll go back into the storage bin along with the rest of them probably

For me I enjoy learning a bit more each time I do one of these jobs .

[cb4ever104]

Just an update to say that I haven't been able to finish this off yet . I've been away for a bit . I'll post back with some final photos once I get the few hours I need to finish it .

[cb4ever104]

Thanks

Well. Job done. Took a while , but I had to stop and start all through this one. Thanks to Sue for all the work she put into this , and for sharing it. The only thing I'll remember to do next time is cut and prepare the PCB "before" putting the components in. Had to tweak the VCO a bit to get it to cover the HI band . All my offsets were about 70hz off , which I corrected with the app. I left my Clarifier as "fine" and locked (RX Only). I might put a dual pot in someday and have both coarse and fine. My 4 front switches do HI , +10Khz , +5Khz and -5Khz. I'll use my label maker to add these to the front bezel. I might run a counter cable in as well before I finish.

IMG_20211207_143120.jpg

Sammy

[lbcomms]

Good stuff, glad it all worked out for you, do a pic of the finished radio and post it here. Next, the final chapter in the trilogy, the MB8719/34...

[cb4ever104]

Finished photo

IMG_20211207_202156.jpg

[lbcomms]

Looking good!

Just bought a side mic Cobra 148 to finish the trilogy off, new years project if it arrives in time...

[cb4ever104]

a side mic Cobra 148

Much better than the later Malaysian / Chinese versions .

[astradyne]

a side mic Cobra 148

Much better than the later Malaysian / Chinese versions .

Didn't these use the Ranger 8719 chip which differed to the original? My Galaxy DX 2547 has this Ranger 8719 and Nick said it was a bugger to work on.

[Otter]

Didn't these use the Ranger 8719 chip which differed to the original? My Galaxy DX 2547 has this Ranger 8719 and Nick said it was a bugger to work on.

I think the 64/128 pin on the Ranger 8719 doesn't work, so expanding the radio by playing with the binary programming pins is limited unless you swap the PLL.
This expansion doesn't touch the PLL programming, it alters the reference frequency, so it shouldn't be a problem.
*Disclaimer* I have only read about the Ranger 8719 - I have no experience.

[astradyne]

Didn't these use the Ranger 8719 chip which differed to the original? My Galaxy DX 2547 has this Ranger 8719 and Nick said it was a bugger to work on.

I think the 64/128 pin on the Ranger 8719 doesn't work, so expanding the radio by playing with the binary programming pins is limited unless you swap the PLL.
This expansion doesn't touch the PLL programming, it alters the reference frequency, so it shouldn't be a problem.
*Disclaimer* I have only read about the Ranger 8719 - I have no experience.

I read about the Ranger 8719 prior to sending the DX2547 down to Nick. You can get extra frequencies by manipulating the 8719, but the channels would be all over the place.

Nick fitted a pic to the radio (originally on 40 channel cept) plus an FM board I sent him. He struggled to get mid/high and UK out of it. To quote him, he said "if I never work on one of these again it will be too soon".

[cb4ever104]

Didn't these use the Ranger 8719 chip which differed to the original? My Galaxy DX 2547 has this Ranger 8719 and Nick said it was a bugger to work on.

Not that I've seen tonnes of them , but all of the Taiwan and Philippine 148 GTLs that I have seen have always had the MB8719 fitted .

To quote him, he said "if I never work on one of these again it will be too soon".

Pretty sure he told me that a few times as well in the past

[astradyne]

Didn't these use the Ranger 8719 chip which differed to the original? My Galaxy DX 2547 has this Ranger 8719 and Nick said it was a bugger to work on.

Not that I've seen tonnes of them , but all of the Taiwan and Philippine 148 GTLs that I have seen have always had the MB8719 fitted .

To quote him, he said "if I never work on one of these again it will be too soon".

Pretty sure he told me that a few times as well in the past

I think the later front mic version (China?) of the 148 GTL has the Ranger MB8719. Why Ranger felt the need to change something that was time proven is beyond me. If it ain't broke...

[Otter]

I think the later front mic version (China?) of the 148 GTL has the Ranger MB8719. Why Ranger felt the need to change something that was time proven is beyond me. If it ain't broke...

It's probably to do with getting it FCC certified. They don't like radios that can be expanded.

[cb4ever104]

It's probably to do with getting it FCC certified. They don't like radios that can be expanded.

I remember reading that they (the FCC) weren't able to do anything as long as the original specs of the "already FCC approved" radio were never changed . The 148 GTL was a good example of this . It never changed , so it never had to be recertified . Saying that I'm only talking about the older ones . I'm not sure if the radio needs to go through the same process if the mic is moved from the side to the front .

S.

[lbcomms]

You can get extra frequencies by manipulating the 8719, but the channels would be all over the place.
<...>
He struggled to get mid/high and UK out of it. To quote him, he said "if I never work on one of these again it will be too soon".

This expansion method doesn't touch the programming pins of the PLL, as far as the 8719 chip is concerned it's still a stock 40 radio, so it should work equally as well as it will on the Uniden board - providing it uses the 11.325 downmix crystal frequency. And if it uses a different crystal, it's just a matter of making a different firmware / app version to suit.

An earlier prototype on a later model radio using the same method, but that time to cure the drifting they are well known for:

viewtopic.php?f=53&t=55913