• You can now help support WorldwideDX when you shop on Amazon at no additional cost to you! Simply follow this Shop on Amazon link first and a portion of any purchase is sent to WorldwideDX to help with site costs.
  • Click here to find out how to win free radios from Retevis!

Can A Person Install A Frequency Counter In A Cobra 29

How about just buying a new backlight and save the hassle of not ever getting the right answer...

To help you out, older Frequency Counters used in the Galaxy, Uniden and Cobra sets, per what @nomadradio was making a suggestion to, the IF of each radio a Frequency counter that uses the IF - TRANSLATES that IF into a number, being your Frequency.

Problem is, many radios used a different loop frequency, until just recently - when most are now stabilized to the 10.240 MHz standard although a few outliers like those from President. They made rouge versions of the Cobra 148 GTL - but called it DX.

As you will find out, that counter was pretty versatile.

The counter you are using now, from Galaxy that FC347, is Pre-programmed - it won't work on your Cobra very well. Why? The loop the FC347 uses is based upon a 13MHz Crystal, so it's loop frequency is a DIFFERENCE between the PLL IF loop and its' own loop - with the "base" loop of another set. IT's Galaxy's way of doing things...

So they do offer the FC347 but when you use it in Cobra or Uniden, you'll need to set some jumpers on the board so it knows how to sample, count and calculate properly.

To help if you do your research on the FC347 - yes, IT SHOULD work, but you'd still be better off using the main faceplate unless you've done away with it and want to use a Frequency counter with your Delta Tune as a Slider - well I can't blame you for trying - Good Luck!

You might want to try Para-Dynamics PDC-356 instead.

Wanted to give you a piece of history though, the Para-Dynamics Offered a Frequency Counter that used BCD switch setup to alter the count the Sampler did, for its' calculations - a Rotary BCD switch set of 4 were used in this old fossil ... PDC-256...
View attachment 43044

PDF Attached...
Thanks I'm getting to understand it a bit better now. The problem is I've searched for the display but can't find it any place. From what I have read it takes the Cobra p/n 306-003. But then again can't find it but I'm not very good on searching things lol.

Thanks again to everyone that's helping me I'm very grateful...
 
Ok, if you've lost your Display - meaning even shining a bright light onto the Front Panel and you can't see this...

upload_2021-2-9_9-22-1.png

Then I can't really help you...The "serial data" cable that runs thru the CPU module that piggybacks that display backlight / LCD display - if that is damaged there is still hope for it, but that means you ship it back to Cobra and since you've Modded it - you have to remove all those mods done - take the hit on the wallet - buy it back after service and then re-install all those mods...

You can find "flat-ribbon cable" but to make it work correctly it needs to be stripped (the foil exposed from the insulator) but it needs a tool - or a razor blade (which it has in it) but it requires a FLAT and Smooth surface run to break the plastic off the foil - it's a stripper machine which for a 1 time use is a little cost prohibitive.

  • If you are building your own, a Cobra 29 channel BCD with built in Display can work just fine in those units.
  • The Main PCB is a Cobra 29 board, you just drill mount and fasten all the needed hardware into a front panel bezel for it
  • The LX display is the "Computerized" switching that you have to do by hand - which most of us do with ordinary Cobra 29's everyday - you use the Big Knob to enable and select the options and features, everything else is still analog, Volume, Squelch, RF gain even the Delta tune.
  • The Talkback and PA relays are done thru the CPU - if you're into that sort of thing.
  • The PLL in many of these still uses Parallel Data (That Rotary Channel Knob)
    • Sidebar, Cobra is moving away from this BCD approach and going to Serial PLL so you know

The Display is actually a series of LED's - Full-Color meaning there's 4 LED's on a mounted module - it uses a "frosted plastic" panel much like those used on LCD Computer Monitor and Laptops these days.


upload_2021-2-9_9-17-48.png

This is for the Rest of us.
 
  • Like
Reactions: NZ8N
Ok, if you've lost your Display - meaning even shining a bright light onto the Front Panel and you can't see this...


Then I can't really help you...The "serial data" cable that runs thru the CPU module that piggybacks that display backlight / LCD display - if that is damaged there is still hope for it, but that means you ship it back to Cobra and since you've Modded it - you have to remove all those mods done - take the hit on the wallet - buy it back after service and then re-install all those mods...

You can find "flat-ribbon cable" but to make it work correctly it needs to be stripped (the foil exposed from the insulator) but it needs a tool - or a razor blade (which it has in it) but it requires a FLAT and Smooth surface run to break the plastic off the foil - it's a stripper machine which for a 1 time use is a little cost prohibitive.

  • If you are building your own, a Cobra 29 channel BCD with built in Display can work just fine in those units.
  • The Main PCB is a Cobra 29 board, you just drill mount and fasten all the needed hardware into a front panel bezel for it
  • The LX display is the "Computerized" switching that you have to do by hand - which most of us do with ordinary Cobra 29's everyday - you use the Big Knob to enable and select the options and features, everything else is still analog, Volume, Squelch, RF gain even the Delta tune.
  • The Talkback and PA relays are done thru the CPU - if you're into that sort of thing.
  • The PLL in many of these still uses Parallel Data (That Rotary Channel Knob)
    • Sidebar, Cobra is moving away from this BCD approach and going to Serial PLL so you know

The Display is actually a series of LED's - Full-Color meaning there's 4 LED's on a mounted module - it uses a "frosted plastic" panel much like those used on LCD Computer Monitor and Laptops these days.


View attachment 43050

This is for the Rest of us.
Thanks for the info I noticed something kinda strange well to me it is, it has 2 sets of relays next to the display when I turn the power on I hear them clicking. What are the relays for?
 
Can you tell us
Is the display working, or is the back light just out?
As Andy asked, if you shine a light onto the front of the display while the radio is on, do you see anything or is it blank?

73
Jeff
 
Cobra part number 306-003
I would call cobra and ask them first, they may have the part available.
800-964-3138
Let us know what they say.

73
Jeff
I called yesterday and was the 68th caller waiting so I requested a call back, well no cal as of yet. I called back this evening I was the 96th caller waiting n again requested a call back, still waiting...
 
  • Like
Reactions: AudioShockwav

dxChat
Help Users
  • No one is chatting at the moment.
  • @ Mark Malcomb:
    Hello BJ. Been a long time since I've been on. You doing well? Mark Malcomb
  • @ Naysayer:
    I’m
  • @ kingmudduck:
    Hello to all I have a cobra 138xlr, Looking for the number display for it. try a 4233 and it did not work