President Ronald (EPT360011Z) PLL Alignment wrong voltage

[Phuture]

Hi,

In step 4 of the Superstar 3900 PLL alignment instructions (attached) it says the voltage on channel 40, band A on AM "must be 2.2VDC approximately" but on my President Ronald it's only 1.34V. Setting 5.0V on channel 1, Band F on AM sets easily enough but I'm just concerned I'm too far out with the voltage found on channel 40, Band A. Does this look too far out for there not to be a fault somewhere, and ,if so, any ideas where I should start carrying out tests?

Thanks!

[13EL121]

If the PLL locks, it should be no problem. But I would replace all electrolytic caps in the PLL area. Maybe replace all 10v caps in the radio. They are known to fail after all the years.

[Phuture]

Hi 13EL121,

Thanks for your message and advice.

Yep, I had already carried out the cap replacement and I thought that might be the reason the voltage dropped as I think (but not completely sure) that the voltage was within a few decimal points of 2.2V when I first tried to align the radio. I bought general purpose electrolytics, but they're low ESR so I hope the latter hasn't affected anything adversely. Yes, the PLL locks at the top and bottom end of the radio's frequency range so it would seem to be okay but I wonder why it's quite a bit off 2.2VDC at the bottom frequency end.

P

[13EL121]

OK, one time I had a bad PLL IC, but the radio didn't work either. Check the 10.240mhz reference xtal maybe. But if the radio works in all bands it should be no problem.

[Phuture]

I think it seems to be okay but I need to complete a full alignment to be certain.

Thanks for your advice. Hopefully the alignment will prove the radio to be working well.

Cheers

[14CS06]

Hello

Service manual here

http://78roger.free.fr/president/ronald.htm

http://78roger.free.fr/president/manuel ... ronald.pdf

@+
Claude

[dt307]

split the difference 4.9v on ch 40 and 1.44v ch1 if you get good vco lock on all channels at the top and bottom

stick a fork in her....she done

[Phuture]

Thanks, 13EL121 and dt307, I don't see a problem with the VCO locking on Tx or Rx so I assume the voltage extremes are okay. Thanks again. However, I have discovered a gremlin that is related to the PLL or frequency counter that perhaps you may have some insight into but I will leave that for a later post as I need to note the symptoms fully to be able to describe the problem.

Claude, thank you for your links. I got the French service manual (same one as in your link) a while back from http://cbradio.nl/president/president_ronald.htm. Since the French service manual appears to be the only version of the service manual specifically for the Ronald 1 (6-band) and Ronald 2 (5-band), I thought I'd give a go at translating it so I could see if there was anything different or in addition to the Secret CB Superstar 3900 alignment procedure (as attached earlier). There aren't many differences but the most notable is the bias amperage values, which I decided to use at least until I finish the alignment and test the radio. If all is well I'll leave them unchanged; otherwise, I'll use the Secret CB amp settings for the biases. I've been following my translated version through the alignment and correcting errors as I go, along with adding anything better clarified or useful from the Secret CB 3900 procedure. Perhaps you would like to see a copy once I have completed my Ronald alignment here? I will post the translated document if it is useful to anyone to compliment the Secret CB alignment procedure or just for comparison since it's more or less a direct translation.

The reason for adding to this post was simply to ask what modulation percentage should be used when setting S-9 at 100uV (as attached in step 5 on the secret CB receive alignment procedure) as neither the French or Secret CB manuals state this? Is this modulation percentage 30% or some standard modulation level?

Thanks all!

[Atomic Cafe]

Hello

Service manual here

http://78roger.free.fr/president/ronald.htm

http://78roger.free.fr/president/manuel ... ronald.pdf

@+
Claude

THANKS CLAUDE! I've been looking for this manual for the equivalent Galaxy 2100 radio.