CB spares
 

Does anybody know where I can obtain spares for a 1980's Cybernet based CB, Rotel RVC240, Harvard 420M, Fidelity 2000 etc.
I am after a green channel number display.
There are ones on Ebay but I have bought one and they appear to be not suitable, they have 2 dots and do not work in the older radios.
The type I am after does not have any dots just the 8 8 led segments.

Thanks
Mike

Re: CB spares
 

Is it the display PCB or just the 7-segs you are after?

Re: CB spares
 

I admit some photos would have helped.
Here we see a new 7 segment 2 digit and 2 points unit which does not work in the radio.
It was sold as suitable for Cybernet radios, but it doesn't work.
Attachment 192085

This is an original identical one in another radio. It has 2 rows of 8 pins the same as the one above, but there is no point/dots on this unit.
Attachment 192086

What I need to repair this CB is a replacement double digit 7 segment LED channel display suitable for these older CB radios.

thanks
Mike

Re: CB spares
 

You could try contacting Knights CB. I have not been for some time, but I remember when I did they were very helpful:

https://www.kcb.co.uk/

Re: CB spares
 

Knights CB couldn't help, but thanks for the suggestion.

Mike

Re: CB spares
 

Forgive me for asking, but are you sure it is the actual 7-segment display which is the cause of the original fault? (Maybe you have a segment which is not lighting?).

On this generation of radios the voltages to light or not light the individual channel display segments are individually supplied to the segments via series resistors through contacts on one wafer of the channel switch - the other wafer generates the parallel channel select codes which are fed to the PLL IC.

Where all things are equal it is just as likely for the problem to be with the channel switch or with the associated series resistor, assuming you have one segment not lighting.

Re: CB spares
 

I have one here, but it's red. Green was often used in the Midland brand CBs.

Re: CB spares
 

I have an original Cybernet 3000 service manual here - interestingly with Goodmans branding on the manual only, so I guess they must have been the importers of the Cybernet 'own brand' branded 1000, 2000 and 3000 models.

The 1000 and 2000 were 'mini' radios and used smaller displays but the 3000 was a full sized set, notable mainly for having a LED meter instead of an analogue meter - not an improvement in my opinion.

As you may know the Cybernet own brand models were one of the relatively few Cybernet models which, like the Rotels, used green channel display LEDs.

The manual includes a full parts list so I looked it up and the Cybernet part number of the green common-anode channel display is 'QL * SL2271', description 'SL2271 Green Com-A'. I'm assuming that the SL2271 part is the manufacturer's own part number but if so, good luck finding that on the internet. I failed miserably. Maybe someone here knows which optoelectronics manufacturer prefixed their part numbers with 'SL' - likely to be Japanese, as that's where the radios were made.

I'm going to a rally on Sunday so I'll keep an eye out for any wrecked CB chassis lurking in boxes. I looked around, there are a few Rotels available online, not particularly cheap and probably too good to take apart for spares. I think the Rotels are the nicest looking UK Cybernets from that era, their styling looks good even now as they don't have the acres of 'Chrome plating' which dominated the CB styling of that time.

Re: CB spares
 

Hi SiriusHardware
I have taken the one out of my spare Harvard 420M (almost identical Cybernet board) and the Rotel channel display now works perfectly.
But this now leaves me with a otherwise good Harvard with one segment not working.
If you happen to see one of these old 80's Cybernet sets/chassis going cheap (under a fiver) I would be most grateful if you could grab it for me.

Hi Restoration73
If nothing else turns up at the rally that SiriusHardware is attending on Sunday and your red one is spare I may be interested, if it is the correct type and off one of these early CB radios.
I dont think it would look too out of place if it had a red LED, it would match the signal/power meter on the other side of the rig.

Thanks guys.

Mike

Mike

Re: CB spares
 

Just an idea. Try Wagner in Australia, they seem to stock a vast range of spare parts for consumer electronic products.

Kevin

Re: CB spares
 

Come to think of it the Yorks (861, 862, 863 etc) were another green-display UK Cybernet variant. Unfortunately they are quite fondly regarded and never especially cheap. I'll keep an eye out on Sunday.

Re: CB spares
 

Lots of Green LED readouts on Amazon both with and without dots but ive no idea if they would be suitable .

Re: CB spares
 

'skip - were these twin (two digit) displays without decimal points which you found?

If so a link would be helpful, I could not find a single green twin display without decimal points. It would be helpful if crackle could tell us the required size (height by width) of the replacement displays as well.

crackle, I did remember to look out for a donor carcass today but ironically the very gent who usually does take that sort of thing to the rally decided not to on this occasion, so I drew a blank - sorry.

Re: CB spares
 

What about something like:

https://www.rapidonline.com/kingbrig...isplay-57-0130

or

https://www.rapidonline.com/kingbrig...-digit-57-0166

Go to Rapid and search "Kingbright" for others.

Re: CB spares
 

I'm afraid both of those linked examples (in common with all the ones I can find) have decimal points. The one crackle is looking to replace does not have decimal points and presumably the pinout of these more common displays which do have DPs is incompatible.

Re: CB spares
 

Ah, sorry - I hadn't noticed the needed lack-of-DPness.

Re: CB spares
 

This

https://www.ebay.co.uk/itm/TR321OF-2...Y/163765531539

...looks to be one lacking decimal points. While the main description and picture show it as RED, other parts of the listing describe it as GREEN.

Might be worth dropping a query to the seller to ask which colour it really is / whether he also has them in green. No indication of size either, which is not helpful.

If it's red I would go with the one kindly offered by Restoration73, assuming his is either in or from a Cybernet set.

Re: CB spares
 

Hi
Thanks for looking at your meeting today.
I did see that red one, it looks identical to one I took out of a slightly more modern CB which is a scrapper. (somebody had been making lots of changes to it and wires were off everywhere.)
I must admit I did not try it in the Rotel or Harvard because it was red, but if it works then that would probably be the answer for now.
Thanks
Mike

Re: CB spares
 

I have a number of Cybernet-based (complete and working) sets in my collection, most with red channel displays, some with green.

Since you've highlighted the apparent difficulty of obtaining exact replacements for these radios - like you, I would have assumed they were absolutely bog standard - I asked the seller of the item to add more information about them to the listing, which he has, as follows:

* I originally asked him to state the character height, but he seems to have measured the height of a single segment instead.

I haven't taken one of my own radios apart yet but I've ordered a couple of these displays and will post details of the pinout when I get them, and will also check them against the physical and electrical pinout for the display in a typical Cybernet to see if they actually will be suitable as drop in replacements.

He doesn't have them in green, unfortunately.

Re: CB spares
 

I have taken a photo of the display in question.
I have to admit that apart from the colour and identification number it looks identical to the red one on Ebay.
Attachment 192207

Overall dimensions. w22, h16.1, thick8.3, pin spacing 2.15, between rows of pins 12, all mm
How do I tell it it is common Anode?

I too had a reply from the seller, below.

Hello ,
This is the only double one with no decimal place we have.
We do have a single green one - 'DLG7673' but probably not suitable if your after a double.
To be honest I have had a look at the old cybernet CB radio and it does look pretty identical. This 7 seg display will be from the 80's 90's as its unused old stock that we've had for some time!
I have updated the listings with dimensions etc which will hopefully help you if you have the physical item :
2.7mm long, 2mm wide, 1cm thick, pins = 5mm
segment size = 8mm
Pitch between pins = 3mm
I see a few available on ebay but mostly red or blue in colour. Might be worth a shot?
I will refund you in full if you return it, I know this is faffy but could solve your problem. An option anyway,
Kind Regards



Mike