Pro-95 Frequency out of alignment

[Cressida81]

I have had this pro-95 since about 2007 or so. Its spent most of the last 8-9 years stored away.
Now I've gotten it out as a backup to scan my local ham radio repeaters while I'm talking on another one. It was not picking up the repeaters I programmed in.

I started doing some testing and found that the frequency is off. I verified with my own ham radio equipment.

For example on 146.52 If I set the scanner there and transmit on my handheld it picks up nothing. If I key down and continue transmitting while it scans upwards it doesn't break squelch until it hits 146.745.

Is there any kind of alignment that can be done or has this unit just hit its end of life?

Thanks.

 

[kruser]

How far off does your local NOAA WX frequency need to be tuned before it sounds on freq on your Pro-95?

 

[pro92b]

Your PRO-95 is way off frequency and it may not be possible to adjust it back that far. See the thread at Retune out-of-tune Pro-95 scanner? (off by .0125mHz).

 

[Cressida81]

How far off does your local NOAA WX frequency need to be tuned before it sounds on freq on your Pro-95?

I was just doing this test with the WX stations.

The only WX station it gets here in my office the pro-95 says is WX2 162.425. But when verifying on my ham radio handheld what i'm ACTUALLY getting is 162.400.
I opened up the case and attempted to adjust the trimmer cap. I can make its reception of what it thinks is WX2 get all static, but when i change the pro-95 to WX1 (162.400) no amount of adjustment on the trimmer will bring it into focus.

So, for now what I've done is I went back to what it thinks is 162.425 and used the trimmer to get it centered right on that frequency. So at least now I know its just about exactly .425 off. I could probably just enter in all the repeater frequencies with +.425 and see how that goes.

Disappointed its failed so hard when some of those old scanners are like 20 years old without issue.

 

[slicerwizard]

425 kHz off? Isn't it off by 25 kHz?

And I doubt that the frequency error will be constant. At higher frequencies, I'd expect a larger error. Try tuning to 440 MHz...

 

[Cressida81]

425 kHz off? Isn't it off by 25 kHz?

And I doubt that the frequency error will be constant. At higher frequencies, I'd expect a larger error. Try tuning to 440 MHz...

Yes... not sure why i left the 4 in there. No wonder I was struggling. 0.025.
I'll have to do some further testing during one of the active times on the repeater to dial in exactly what I need my offset to be on VHF and then UHF when the 440Mhz repeaters are in use. I don't ever use it for 800Mhz anyways.

 

[tvengr]

Crystals can go bad. They usually drop in frequency as they age. It may be too far off frequency to bring it back using the trimmer. Disc capacitors can open. There could be a another bad component in the oscillator circuit other than the crystal. I am not familiar with that particular scanner. Usually, there is a voltage regulator for the oscillator. That could be bad. The voltage is very critical in maintaining the proper frequency.