The Defpom Forum, for RadioMods, S&M Software and Music by The Defpom

zodiac

Well it looks like the adjuster of L21 is working as you said it is adjusting from 17.08 to 17.92. Check the binary pins of the PLL on channel 19 mid band, you should have pins 10,13,15 and 17 at about 8v, that's a count of 149 in binary, plus the 10.695 crystal plus the 15.000Mhz crystal giving you...

zodiac

Animal,
Put the counters probe to TP3 R84 and adjust L21 for 16.490 on channel 19 Mid band in AM or FM in RX mode.
Let us know if it does adjust to the correct frequency.
You haven't said if it's off on all modes or just AM/FM.

Dave.

zodiac

Alex,
Check L123 4.7uH coil at the front corner of the board, you should have 13v both sides of it.
Dave.

zodiac

Both radios were made by Cybernet about 25 to 30 years ago, they both use the same PLL the o2A and can be banded without any problems.
The Nato 2000 is the better of the two, the other is CRAP.
Dave.

zodiac

You say the driver and final are OK and theres the correct voltage at both collectors.
Is there any current being drawn by them in TX ?.

zodiac

Check the voltage the PSU is set at, it may have been turned up too high, or try it on an external PSU to see if it still does it.

Dave.

zodiac

Uncle Ray,
I've got a schematic diagram for the WKS 1001, with the MC145106p PLL in it if it'll help.

Dave.

zodiac

The mike wireing is on the Schematic diagram, you'll find it on cbtricks.com under radio information.
If it's the mike plug your looking for it's,
Pin 1, white, audio.
2, black.
3, red.
4, blue.
5, screen.
6, brown.

Dave.

zodiac

Steve,
Just replace the crystals and adjust the VCO slightly.
20.555 is the super high crystal, I've got a bag full if you need any.

Dave.

zodiac

Thank's Rick,
I was tempted to give him your name and address to repair it.

I changed the rectifier on this PSU about 5 years ago and fitted lucar connections on the leads so it wasn't that bad to work on.

Dave.

zodiac

Thanks for the links, I allready fixed it after replacing all the transistors and fitting sockets for the two IC's and both the IC's while I was in there.
The fault was the 47000uf @35v electrolytic it has a broken terminal.
Now the problem is finding a replacement that'll fit in there.

Dave.

zodiac

timrim,
Did you ever find a schematic diagram for the PSU, as I have a Palstar PS-30M in need of a schematic.
They come under three names that I know of, the Watson, Manson and Palstar.

Dave.

zodiac

Yes that's correct but with the PLL removed theres nothing to pull the codes to ground if the PLL is at fault in any way, as you did say the PLL had a hole in it.
Give it a try and let us know the results.

zodiac

angus,
Remove the PLL then check the binery codes again, if they are correct replace the PLL with a good one.

Dave.

zodiac

Yep, that's the book.
Dave.

zodiac

Yes it should.
Angus to help us help you can you tell us what the number is on the Eprom.
2716/32/64/128/256 or it may have a C in the number like this 27C16.
Dave.

zodiac

timrim,
Take a read of The EPROM Data book by Martin T Pickering, it will give you a better understanding of what you need to know and what radios will take an Eprom, or should I say what PLL's you can use an Eprom with.

Dave.

zodiac

angusuk, The channel switch side of the Eprom will always have the same codes going into the Eprom, they never change with the bands. Check to see if the 5v that run the Eprom are there, it's a common fault with the spectrum Eproms to brake the pins off the 7805 5v regulator and if that's happend yo...

zodiac

Both L45 and L41 need adjusting if it's off all the way through.
I could do it for you but I'm 6 mile NE of Manchester.
Hope you find someone to put right for you.
Dave.

zodiac

I think you'll find you need to adjust L41 the AM/FM coil for the 6 highest bands.
You didn't say if the radio is off frequency on all it's bands or just 6 of them.
Dave.

zodiac

I'm a bit confused about the radio, is it a jumbo with another radio fitted in it ?. If it's a 3900 type board the VR's for RX are VR1 and VR2, one for AM/FM and the other for U/LSB. Is the radio off by one channel on all bands on AM/FM and how many bands does it have as I've not seen the radio. If ...

zodiac

You have a PM.

zodiac

The info you need is all on cbtricks.com
Click on radio information then Uniden then AX144.
Dave.

zodiac

With the KC shift set in the notch and the clarifier lined up with it you should be on frequency. All 3900's don't line up spot on 12 o'clock like the old 148 GTL DX there slightly off the 12 o'clock position, that's normal for the 3900.
Dave.

zodiac

If the diode has gone short circuit then how come the fuse hasn't blown.
You have checked the fuse to see if it's the correct value.
Dave.

zodiac

Take a look on www.cbtricks.com under radio information
Theres a schematic diagram for the 1-630.

zodiac

But how do you get on the 5's, you'll only have the zero's.
You'd need to be able to switch from one to the other not just replace it.

zodiac

Shaun,
It's been a long time now but I think it's only about 3.1/2 KC's in total without having to change or add components.

zodiac

Have you adjusted the FM discriminator coil to try to inprove the receive ?, if it's not adjusted correct everyone will sound off frequency.
I don't know the coil number in that radio before you ask.
Dave.

zodiac

In SSB mode you do have to turn the volume contol up that's normal and I wouldn't worry about it but it may need a tune up on the side band receive coils, theres only two of them L17 and L18L if I remember right.

zodiac

Check the 10th bit of the LPP, Pin 17 to see if it's being switched on and off as you go through the channels.
It looks like you may have a broken connection between the channel change switch and the PLL's pin 17 as the 10th binary bit is missing.
Dave.

zodiac

A Mosfet is a replacement for the final output transistors that are no longer made and getting harder to find.
They are NOT a direct replacement you need to chenge some other components as well.

zodiac

NightRanger, It may be a bit late but D32 in the MK2 Adams PC 346 is part of clarifier being unlocked and that may be reason your having trouble getting on frequency. The full unlock. Desolder one end of R117, D30 and lift them out of the holes or remove them both. Remove the wire from next to C110 ...

zodiac

It's 181

zodiac

Don't fit an electrolytic cap, replace like for like.

zodiac

Jimmy,
It cost less to buy a side band radio with FM on it than the boards required to covert or add FM.
Keep it as it is, there a good radio for side band use and very very well built.

Dave.

zodiac

Have you had a look inside of it to see if there's any name or ID printed on the board.

zodiac

Jimmy, Yes to both your questions but you wouldn't want to pay for the FM conversion, very expensive on that radio because of the 8MHz crystals instead of 10.695MHz like more modern radios. The Eprom could be re programmed as long as it's not a once only program Eprom (no window in it). If it's a 27...

zodiac

Well you could use a tin can but count your fingers first.

zodiac

It does work. I've done it to many a home base radio when I've had to fit a new transformer other than the original type.

zodiac

Screen the transformer with copper foil or thin copper plate and solder it to the case of the transformer.

zodiac

It could be that the 1969 you fitted is a fake or a poor copy.
I would say that the driver is working fine as you are getting 6w from the radio.
As for fitting a resistor from the final to the driver, i can't say.
Dave.

zodiac

Hi Dave,
Try adjusting the Rf power at VR203, front right hand corner of the radio.
Dave Oldham.

zodiac

Check for a shorted electrolytic capacitor close to the audio chip.
Had the same problem with a Uniden radio.
Dave.

zodiac

Joe, Did you use the SWR meter and check the SWR again when you fitted the Tornado and was it lower than before with the other aerial ?. What I'm getting at is, if the SWR is too high it will cause the meter to read a higher output than what is going out because of the bad SWR. The DX27 is a much sm...

zodiac

Hi Joe,
Welcome to the forum. When you key the mike does the needle go over to the right of the meter into the red, or does it go to the left.
Dave.

zodiac

Smokinjoe,
This is the output stage of the PC 385.

zodiac

Shaun,
Your right D31 is the varactor diode. You could also try a ITT410 out of an old Cybernet multimode radio but 10KCs of total slide, i don't think so.

zodiac

Yes it does work.

zodiac

Hi Dennis,
It would help if you told us what the radio is, then someone might have the answer your looking for

.

Dave.

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