Galaxy Pluto... Where do I begin?

[MightyMo]

I recently acquired a Galaxy Pluto. Traded a 29LX for it. The problem is it's broke. I've only done things with Cobra and have little technical experience. Any help would be appreciated. (I haven't had a chance to open it up yet). I'll do that in the next couple of days.

Symptoms:
RX only works on FM mode. (No static on AM, USB, LSB)
Standard 4 pin cobra mic won't key the radio. (RX/TX light does not change)
Changing channels does not change frequency displayed on counter
Changing band switch only changes frequency when changing from B to C (A and B bands display same frequency. C, D, E, F bands display same frequency)
+10KHz does nothing
Clarifier does not change frequencies

On the plus side, chanel indicator works. Meter light works.


Thanks

[sonoma]

1st off it sounds like the PLL is not locked on. you will have a nice can of worms here when you start. type in this link what problems you are having and it may help you find your problem

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[sonoma]

forgot to tell you to touch up the solder joints at the 10.240 crystal and the PLL and VCO areas. even the 8 volt reg areas. the age of the radio could have some 10 volt caps in the 8 volt section that are going bad. I would change all the 10 volt caps to 16 plus volts before I did any thing else to it. the radio is pushing 25 plus years of age.

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[MDYoungblood]

I'm surprised to hear the FM is working, the Pluto was one of the original conversion radios with one of the worse boards made. It probably has cold solder joints all over the place and that is where I would start, get a good pair of cheater reading glasses and a nice hot soldering iron, sit back, take your time and touch up most of the joints on the solder side of the board. Next since the FM is working start with that and use the spec link sonoma posted.

3's

Greg

[MightyMo]

Thank you for the help guys! Couple questions.

Why change 10 volt caps for 16 volt caps? Are the 16 volt caps just an upgrade or do radios need higher caps as they age?

The link Sonoma posted is for Galaxy DX radios. Galaxy Pluto is not listed on the Galaxy schematics page. I thought I read somewhere that the Galaxy Pluto wasn't actually made by Galaxy (Didn't catch who it was made by) and it's not a DX class radio. Not sure if this is accurate, but any idea where I could find user and/or service manuals for this radio? Some of the info on that link did look useful and relevant to me. But it obviously lists parts as labeled on the board of that specific radio. Because I'm new at this, I'm going to have a hard time finding the same parts in my radio if it's labeled differently. I did see the Galaxy Plus looks quite similar with the exception I don't have a PA function, where it has E-Tone I have Mic/RF gain. When I open the radio, I'll compare board layout and see if it's close to mine.

Any idea what the frequency range of this radio is supposed to be (unmodified)?

When I say FM recieve works, without an antenna hooked up, there is background noise that is not present in the other modes.

This is my first experience with a radio outside of the CB band. Can I use the same dummy load to test this radio as a regular CB?

Where do you guys get your components? (Resistors, caps, diodes, etc.) In the past, I've just used Amazon or eBay. But there have been a few times where I can't find exactly what I'm looking for. Radioshack has all but disapeared and is still limited. Is there a one-stop-shop out there (online) for this kind of stuff?

Thanks again.

[sonoma]

from the age of the radio caps start goinjg bad. the 10 volt are on the 8 volt rail and they are rated at plus or minus 20 percent. they all break down over time and the 10 volts go 1st. put 16 volts in place of the 10 volts just to have some head room for the caps. you can use 25 volts also. just do not put 10 volts back in there. just like a car with a tach it shows 6,000 rpm but you do not waqnt to run it at 6,000 grand because it will blow up on you. the factory puts the cheapest part in a radio to start with for cost.
using the galaxy symptoms and cure data base will help you get ideas as to what could cause your problem. do not start thinking its not a galaxy and discard the info on that data base. years ago a galaxy tech use to keep that updated for galaxy problems and it does help. look at what board number is in the radio then compare it with the ones on cbtricks.com to get you in the ball park. do not remember what board is in the radio but if it is a 360014 board there is a bunch of radios with that board. do not get into a mind set of saying mine does not have a mic gain and the other does. you are going to try to fix the main board. like you said the freq counter is stuck on one reading . a bunch of info is in the \data base I left you the link to. get a solder gun out and start checking for bad solder joints in the 10.240 crystal area, the PLL area and the VCO area.one bad joint can kill the radio.
do not know how many over the years that i have found a bad solder joint under the metal ground shield they put on the solder side of the board and the radio comes back to life.
enough info for you right now until you do something.
I buy a lot of my parts off ebay.. on the caps be sure and use the same UF that is in the location you pull a 10 volt out of. going up in voltage does not change any thing other that if the 8 volt rail may actually have around 9 volts on it so 16 volts just gives you some head room for the voltage to the cap so it does not get stress as easy. as MDY stated this radio had a problem with solder and traces. from 1 item I remember with this radio the 8 volts to the front of the radio ran down a thin trace on the very out side of the board. it would get damaged from some one cranking down the bracket screws.it would break the trace and at times pull the solder and trace loose from the voltage regulator. you would lose the 8 volts to the PLL and the front of the radio. the switch for each band on the front of the radio would not have voltage on it to feed each portion of the radio. 8 volts will feed the main board to activate ssb AM and FM.so you need to start checking some of the items mentioned here.

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[sonoma]

if the radio has the 360014 board in it a galaxy 88hml may be what you need. . let us know what board is in the radio.

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[MDYoungblood]

The Super Star SS-3900F is more of a match. The Pluto was a thrown together radio because the manufacturer saw a market for cheap junk in the United States, (yes us Americans will buy anything), the only thing it shares with Galaxy is the name. There were several differently named radios that looked identical but had much better quality to them (they also cost more).

3's

Greg

[sonoma]

if you would look and see what board is in your radio I may have a service manual for it. I have some old ones. all 3 boards I have listed may be in your radio.
PB042
PC999
PB010

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[MightyMo]

I got the radio open tonight. I'll attach some pictures of what it looks like as it sits. Tomorrow or the next day I'm going to start going over the solder joints. I'm not sure where to look for the board name. The only text I see is "E106527 SRF-C 94V-0". Is that it? Also, I can count 5 wires that have been clipped and I can't find the other end. It may be a mod, but I'm guessing it's probably just an unused spot on the wiring harness plug. As far as capacitors go, 99% of what I see is blue. I haven't checked every single one but the ones I have checked are all 25V or 16V. I think they are still original because there are some submerged in the wax stuff. Should I take the time to replace every single electrolytic capacitor?



Thanks so much for your help!!!

My computer is being slow and I need to resize the pictures. I'll post the pictures first thing in the morning.

Thanks again.

[MightyMo]

[sonoma]

well I see the pics but can not tell what trace could be bad. down the side where you have a 3 leg and maybe a 10 leg part mounted to the side of the case. you need to look close and touch up some of the solder joints and on the opposite side is 2 metal shields that you will need to lift and check for cold solder under them. those are the trouble spots a lot of the time. check the trace all the way to the front of the radio .

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[MightyMo]

Eventually accidentally touching the solder side of the board brought back some more RX. Finally (can't remember exactly how it led up to this). I rested my palm on top of the shielding and laid my hand flat on the board for a split second. I noticed the frequency counter was no longer changing. I took it out to my truck and hooked it up and it seems to be working perfectly... on AM at least. It's putting out about 8 watts on AM with the power turned al the way up. I had my wife on a radio in our car about 30 feet away. She said one of my transmissions was faint then grew louder after a second or so. Besides that, I could hear her and she me. I could hear some traffic on AM and LSB but didn't try to make a contact. FM Static is noticeably noisier than AM or Sideband. Is that normal? This is the first FM radio I've had. I'm going to put it back together and put it in my truck for a few days and see how it goes. Problems may return....

I don't know how a radio acts when a capacitor or PLL goes out. Are these symptoms remotely similar to that?

[MightyMo]

(Once again, computer problems. It posted the second half of my post instead of the entire post. Looks like another job for a moderator. Sorry)

So I don't get it. Seems to be working fine now. Here's what happened.

I went over the solder side of the board. I didn't see any cold solder joints that I could identify. Traces seemed to be intact without any noticeable damage. There was one contact pad that had pulled up from the board that I fixed with a small jumper wire but that's it. I touched lots of joints with my iron that looked semi-suspicious but probably didn't need it. I plugged in the radio and there was no difference. I started tapping on the board with my fingers looking for something. I tapped one area and all of the sudden something happened because:
AM static got louder. It caused FM static to be WAY louder and USB had some noise too.
The RX/TX light would switch, but it was slightly delayed going from TX to RX.
The band switch would cause the frequency counter to change as well as the clarifier. BUT it wouldn't stay on a single frequency. It would drift up and down.

I turned the radio off and back on then it went back to the way it was before. All the same problems. I tried tapping the same area but I couldn't get it to happen again. I noticed if I briefly touched some areas on the board, including some of the legs of the PLL chips, I could get more noise through the speaker. But I tried tapping with the eraser of a pencil and I couldn't get it to happen. (Obviously, skin is somewhat conductive so I was shorting circuits instead of connecting cold solder joints).

Eventually accidentally touching the solder side of the board brought back some more RX. Finally (can't remember exactly how it led up to this). I rested my palm on top of the shielding and laid my hand flat on the board for a split second. I noticed the frequency counter was no longer changing. I took it out to my truck and hooked it up and it seems to be working perfectly... on AM at least. It's putting out about 8 watts on AM with the power turned al the way up. I had my wife on a radio in our car about 30 feet away. She said one of my transmissions was faint then grew louder after a second or so. Besides that, I could hear her and she me. I could hear some traffic on AM and LSB but didn't try to make a contact. FM Static is noticeably noisier than AM or Sideband. Is that normal? This is the first FM radio I've had. I'm going to put it back together and put it in my truck for a few days and see how it goes. Problems may return....

I don't know how a radio acts when a capacitor or PLL goes out. Are these symptoms remotely similar to that?

[MightyMo]

Just turned it off and back on... Problems have returned. I'm going to leave it on for a while and see what happens. Do crystals go bad?

[sonoma]

every thing you stated is a bad solder joint problem. are you soldering on the board with power going to it? if you are you will wind up burning out some thing. never solder on a radio powered up. sounds like you are heating a spot that has a bad solder joint since it comes and goes. just keep at it and you will find it.

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[MightyMo]

Ok. Thanks. No. I'm not soldering it with the power on. I really appreciate your help.

So is that text in the picture the board name?

[sonoma]

I do not recognize the numbers in the middle of the board. maybe some one else will know. look under the wires at the front and see what you can see as far as numbers. get it working then we can try to figure out the main board number to align it.
just looking at the lay out it looks close to a galaxy 88.

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[sonoma]

since you have the radio there look at the board layout and part numbers to see if they are the same as your radio.

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[MDYoungblood]

I really wouldn't recommend soldering the board with the power to the radio on, that is a accident waiting to happen, one solder joint cross and the radio can go up in smoke (literally), I normally do a dozen or so spots, check over my work, and then test it out.

3's

Greg

[sonoma]

MDY do you recognize the board number he posted a pic of the board. that looks more like a production run number to me. I am thinking the number should be under the wires towards the fron of the radio. just not sure.

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[MightyMo]

I didn't solder with the power on. When I said I would touch the board. I meant I would touch it with my finger, not the soldering iron.

Yeah. That layout looks quite similar. All the pots and PLL chips are in the same places. There are a few differences. The biggest difference is on the diagram, the lower left-hand corner has some components grayed out. I have all of that on my board.

Check this out: [Please login or register to view this link]
My frequency counter is 24.508 or 25.136 depending upon where the band switch is at. I've resoldered that crystal with no results. Should I replace it and see what happens? Where is the best place to get crystals? I found some used ones on eBay. Would prefer new. Are all crystals similar quality?

[MDYoungblood]

MDY do you recognize the board number he posted a pic of the board. that looks more like a production run number to me. I am thinking the number should be under the wires towards the fron of the radio. just not sure.

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It looks like a Cobra 148GTL DX but a little older model, probably one of the first run PCB, the Galaxy removed the SWR calibrate pot and added a double pot for the echo/delay.

3's

Greg

[sonoma]

do not change out crystals and other items. you need to just set there and clean up solder then resolder a joint if it looks bad. but do touch up ever joint you can see on the board. do a few then turn it on and see if it is any different. when I say some thing like resolder in the crystal area I do not mean just the legs of the crystal. touch up all the joints in that area. you said you once had it trying to work. that tells you you are getting close so do as MDYoungblood mentioned at the very 1st of this post, touch up every solder joint on the board if you have to. this is why a shop charges so much to work on a radio because they will work on it for hours trying to find the bad solder joint. I know my buddy still has a shop and if he tells the customer he had a bad solder joint and he charges 50.00 for 8 hours worth of work and all the customer heard was a bad solder joint and think all he should charge is 5.00 to repair it. I was at his shop one day and charged a guy 40.00 to repair the cobra 148 and the guy had a fit and said he could buy a working used one for that. and I know for a fact he worked on the radio for over 2 hours and had to repair solder joints and replace a driver.

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[MightyMo]

Ok. I'll keep at it. I'll start over and do every joint this time. Like I said, I did several last go round. I even redid the solder around that crystal twice with no change. The next couple days will be busy so it won't happen until next week. I'll post on here if anything changes. Thanks so much for your encouragement and help.

PS I can't find any other text on the board. I looked all under the wires on the front of the board and on the solder side too. I guess that must be it.