Still not sure where to go from here, taking the center pin out of circuit of tr32 is like removing the modulation limiter. But modulation should peg the meter if removed I'd think. I can set the rf power to 20 watt dead key and will go up to 30 with everything on max now so I have 10 watts of forward swing instead of 5 now lol, this radio should do around 130 to 150 watts. Its definitely something in this circuit were in now.
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Rci 2970 low voltage on pin 9 of ta7222ap
- Thread starter That_guy_in_wv
- Start date
Hello nomad, I use an Astatic 600 watt, SWR, and modulation meter. Over the air talking with others in my area and on another radio there is barely any modulation coming through still, regular modulation is maybe around 30%, and peaks at about 83% with tone or whistle on the meter after desoldering tr32's center leg.
Any ideas on what is all connected in the audio circuits, want to re-cap the radio and have no good schematics online for this EPT295013Z board. You zoom in and it's all blurry. Still very low modulation with everything I've tried that everyone has suggested.
http://www.cbtricks.com/radios/rci/rci_2950/graphics/rci_2950_sch.pdf
The 2950 and 70 use the same main board schematics.
The 2950 and 70 use the same main board schematics.
That's the pdf I downloaded and the schematic is very blurry and hard to see and zoomed in is even worse. Not sure if it's my pdf reader or what.
http://www.cbtricks.com/radios/rci/rci_2970/graphics/rci_2970_main_sch.gif
This one is blurry, in the 2970 directory.
This one is blurry, in the 2970 directory.
Thank you guys for your help, c301 was shorted causing my problem. All modulation has returned and I appreciate your help and thanks again Andy and NZ8N
I was looking at the schematic for the power regulator, and noticed that they had an electrolytic cap 100uF @10v at C301, told WV in a PM to check/change that cap to at least a 16v, and there was the whole problem. A 10v cap being fed 13v through R285 a 470 ohm and R286 a 15 ohm resistor in series from the Power Reg output to this cap, is probably not a good idea.
Now you can re-enable the overmod limiters, and recap it, and do a proper alignment on it.
Now you can re-enable the overmod limiters, and recap it, and do a proper alignment on it.
Interesting...
The only 2950 I still have as a template - marks C301 as C322...
Then looking a date codes, the chassis I have is dated 1996 - which places this radio in a class by itself ... and the schematic I had to go along with it...
The RCI - back then - was the "new" Clear Channel - BEFORE Galaxy got merged with it under it's new umbrella of RANGER Communications - AKA RCI - just the initials...
Back when I got this radio - I was informed that this was going to be one of the last radios that can be called a 2950 - because of the "Amortization" of the stock that the radios are populated with - known as the remaining component lots used up by the factory left to finish assembly of these - will no longer make them.
It's why and how I came across this fossil - because of the very fact, like the HR2510's - were going by the way of the dinosaur - I needed to keep one in OEM condition as much as possible.
I'll leave the rather large files behind here - because someone may need to see an older OEM of this...
The only 2950 I still have as a template - marks C301 as C322...
Then looking a date codes, the chassis I have is dated 1996 - which places this radio in a class by itself ... and the schematic I had to go along with it...
The RCI - back then - was the "new" Clear Channel - BEFORE Galaxy got merged with it under it's new umbrella of RANGER Communications - AKA RCI - just the initials...
Back when I got this radio - I was informed that this was going to be one of the last radios that can be called a 2950 - because of the "Amortization" of the stock that the radios are populated with - known as the remaining component lots used up by the factory left to finish assembly of these - will no longer make them.
It's why and how I came across this fossil - because of the very fact, like the HR2510's - were going by the way of the dinosaur - I needed to keep one in OEM condition as much as possible.
I'll leave the rather large files behind here - because someone may need to see an older OEM of this...
Attachments
C322 is the main input capacitor right off of the power input jack, after the input voltage chokes, 2200uF@16v.C301 is the smaller blue cap (in your 4th pic) that is a little to the front-right of C322 and in front of the front/left corner of RL1, the CB/PA speaker relay. This should be "bumped up" to at least a 16v cap, 25v would be better. It has the voltage from the power regulator to the final(s) being fed to it through R285 and R286 as I stated above. They fixed this problem in the DX series, C260 is a 16v cap, per schematics on CBTricks.
http://www.cbtricks.com/radios/rci/rci_2950/graphics/rci2950_ept295013z_main_pcb_layout.gif
Last edited:
I know you're right...
Just there is history here...
Refer to Post #13 in the thread... I don't need to repost it...I trans positioned in the reply above...My proofreading bad...
It' was the point I was trying to make - the changes everyone sees in the RCI, from the Clear Channel to the RCI / Ranger - at the time of the purchase of that radio I have - Post 13 was a snippet that was the most current schematic THEY supplied. (223 not 322 - the Transposition error - mine)
Nowdays? It's different - and here's where we need to stop and make reverence to Rick Jackson at Euro Radio Co. for his efforts in tidying up a paper trail nightmare of documentation for various radios - we have to thank him for the efforts they and he pursued in getting it right for this.
So those blurry copies and other stuff - Benny did his best in sorting that all out.
I'm glad I kept that radio - it's a piece of history not too many people know about.
And yes, C301 is what it is, but schematically - they wouldn't know where to find it because in their original they supplied me, it was not listed. Bennie has - it; my original I got (Snippet at #13 if it is correct) as the 2900 in the RCI archive he has.
That's all I wanted to point out - and it exploded...
Now I have to get back to work... my apologies guys...
Just there is history here...
Refer to Post #13 in the thread... I don't need to repost it...I trans positioned in the reply above...My proofreading bad...
It' was the point I was trying to make - the changes everyone sees in the RCI, from the Clear Channel to the RCI / Ranger - at the time of the purchase of that radio I have - Post 13 was a snippet that was the most current schematic THEY supplied. (223 not 322 - the Transposition error - mine)
Nowdays? It's different - and here's where we need to stop and make reverence to Rick Jackson at Euro Radio Co. for his efforts in tidying up a paper trail nightmare of documentation for various radios - we have to thank him for the efforts they and he pursued in getting it right for this.
So those blurry copies and other stuff - Benny did his best in sorting that all out.
I'm glad I kept that radio - it's a piece of history not too many people know about.
And yes, C301 is what it is, but schematically - they wouldn't know where to find it because in their original they supplied me, it was not listed. Bennie has - it; my original I got (Snippet at #13 if it is correct) as the 2900 in the RCI archive he has.
That's all I wanted to point out - and it exploded...
Now I have to get back to work... my apologies guys...