Recent content by islander

You probably need to change all those original electrolytics everywhere or the radio will remain intermittent for signals coming from oscillators etc. A check of all the crystals, the 3 legged crystal filter and vfo for rusted legs (glue problem) is probably not a bad idea. Cobra 2000 is a great...

How much is the RF power output on AM and what is the the number on the echo board pcb? The Galaxy Saturns are not all the same and problems arise when the incorrect schematics are used.

Audio chip would probably be the place to start. If the audio in and out match specs that would be good news.

Nice radios, I hope you get it fixed. The one I had on the work bench did not have any exotic problems, just needed some capacitors.

Anyone here ever repaired the IC RP1620 or has the original service manual? I have one on the bench for repair and will take any help I can get.

If your low volume refers to when you are having a qso ,its not normal. Check TA7222AP pin 6 input and compare it with the output at pin 9. If the output is low at pin 9 you have a problem in the rf section probably bad coil. ...RF from a radio in the same room or lightning can destroy them...

I have read the thread. I don't fully understand the complaint. Is the audio also low on the internal speaker? Can you actually copy qso's on the correct frequency. I have one on the work bench today, my board is EPT014810Z made in Malaysia. Yours is missing the last zero. I can check some...

MC145162 PLL PINS 5,11,13 NOT USED PINS 1,2,3,4,5 SERIAL INTERFACE FOR CPU CONTROL BLOCK PIN 12 VDD 5 VOLTS PIN 6 VSS GROUND PIN 16 LOCK DETECTOR (HI = UNLOCKED) REMAINING 7 PINS PIN 7 - 10.1 MHZ OSC IN FROM (Q29) PIN 8 OSC OUT TP14? (near pin 8) schematic lists 2 tp14's PIN 9...

Thanks for the intervention. You are probably spot on. The oscillators are off specs and won't adjust properly. The mixers and other devices are ok . I have removed the shields am down to checking the passive components, so I will give the coils a good look. I need to check with the radio...

Yes, I spent a fair amount of time looking at the voltages mainly the oscillators and mixers but the transistors being used are different. Some oscillators are ICs. I found a schematic for the RCI 5054 which uses the same mc146162 pll but it too has no voltage chart. At any rate the problem...

I have downloaded pretty much every 2950/2970 schematic I could find. My checks so far show that PLL1 will adjust, PLL 2 will adjust but the voltage changes on its own. 10.100 oscillator is ok. VCO 1 should be 38.6950 but reads 35.225 and will not adjust. No output at TP5 ifor usb.am or lsb...

Sorry Robb, I said service manual, I should have added with voltage schematic. The ones at cbtricks and none of the others give the transistor voltage chart. Looks like someone needs to be kind enough to measure theirs and tell me and perhaps I can work a little e=ixr guessing. I will post...

Hi Robb, This is the DX version the rci 2985dx. PLL is MC145162 and as Sonoma pointed out to me the voltage schematic for the 2950DX or 2970DX may help. So if I can find a service manual for the 2950dx,2970dx,2985dx or 2995dx, it should help. Maybe there are other radios using the same pll...

Hi Sonoma, The radios frequency counter will correctly read for example 27.105 and ch 12 but the radio will transmit and receive on random frequencies which roll up or down on an external counter far removed from channel 12 and on 12. The pll voltages are too low but will adjust somewhat...