Hight Voltage hit Galaxy DX 959

chrozell · Post by **chrozell** » Saturday 3rd Mar 2012, 11:18

Radio Make and Model: Galaxy DX 959
PCB Number: EPT6960Z Made in China
PLL Number:
Test gear available: ohm/watt meter
Symptoms: Removed a wire from my power supply and it touched a 110 wire and I heard a loud pop. I had my radio turned on when it happened and then nothing. No sound no lights.
What is working:Nothing

What has been tried: Have 13.8 volts to radio power cable where it plugs into radio. Replaced both IRF520 finals. Found small dark residue by a larger 3 leg chip, located corner by power connector and screwed on side of radio like the finals and is twice as big as the finals, part number B 827 and thinking it might be bad also, but not sure what it is.

Did it suddenly happen ?: yes,soon as the 110 hit no more power.
Anything else that may be of help?: What else should I check out. No other parts show a problem.

sonoma · Post by **sonoma** » Saturday 3rd Mar 2012, 11:29

that is the power amp. check the voltages if only 13 volts change it out and see if it comes back one leg has 8 volts

chrozell · Post by **chrozell** » Saturday 3rd Mar 2012, 11:35

Thanks very much, yep that probably got hit also. Bummer just did the mods on the radio then did not bother to turn it off when messing with the power supply. Wonder why the fuse did not blow and protect the radio? Will check fuse amps.

chrozell · Post by **chrozell** » Saturday 3rd Mar 2012, 11:46

Tested and the power amp has only 8 volts to one leg and that's it. really fryed it this time. Only way I learn. Is there anything else I should check?

sonoma · Post by **sonoma** » Saturday 3rd Mar 2012, 14:01

q54 is the 827 also look at q55 just in front of it .looks like a final.check all the traces on the board.you said 110 got to it and was on.no telling what is blown.I would change the 827 at q54 if q55 looks good since you said q54 has a burnt spot on it. then see what happens.it may start up and run

the back leg should have 13 volts on the 827 chip and 13 volts at the center leg.if no 13 on the back leg you can not have 8 volts.
check the power switch for 13 volts also

chrozell · Post by **chrozell** » Saturday 3rd Mar 2012, 14:48

I checked q54 and it looks ok, what is it? Checked voltage again on q55 and have 13.4 volts on the left leg and slowly increases? the center has 9.4 volts and the right leg closest to back of radio shows nothing. The power switch I think is the on/off switch of radio has 13.8 volts but when I turn on the radio, have no volts? I did the mods using defpom mods page and got a great working galaxy but still waiting on the 754 upgrade mod and diodes for noise blanker and receive increase.

sonoma · Post by **sonoma** » Saturday 3rd Mar 2012, 15:25

chrozell wrote:I checked q54 and it looks ok, what is it? Checked voltage again on q55 and have 13.4 volts on the left leg and slowly increases? the center has 9.4 volts and the right leg closest to back of radio shows nothing. The power switch I think is the on/off switch of radio has 13.8 volts but when I turn on the radio, have no volts? I did the mods using defpom mods page and got a great working galaxy but still waiting on the 754 upgrade mod and diodes for noise blanker and receive increase.

OK look at your voltage at the power supply when you turn on the radio .you may not have a good power supply when you power the radio it could be dropping the voltage, if the voltage drops out at the power supply you may have a bad power supply. if you have to plug it up to a car and see if it works.that would be the last thing I would do is plug it to the car.CHECK THE POWER SUPPLY 1ST'. IT MAY NOT CARRY THE LOAD.also do you have voltage at the regulator q54 when you turn on the radio and lose power at the switch?
what power supply are you using?

chrozell · Post by **chrozell** » Saturday 3rd Mar 2012, 15:33

The power supply is a mega watt s-400, puts out 15.4 volts and steady 36 amps.Its only a week old. The 110 cord plugs just to the right of the dc plug in and should have taped it off when I saw the setup. Good ps but screw in connectors and naked wires for a/c not good. Running a old 23 channel high gain radio and put volt meter on ps and keyed down on radio and still getting 13.75 volts. Will hood it to my car just to make sure, good idea.

chrozell · Post by **chrozell** » Saturday 3rd Mar 2012, 15:57

When I put a voltmeter on left leg of q54 have 13.72 volts and when I turn it on get 13.33 volts at the left leg of q54. I put the radio in my car and get no power,same. What is q55?

sonoma · Post by **sonoma** » Saturday 3rd Mar 2012, 16:15

it is a voltage stabalizer.after looking at the circuit you will never be able to trace this out unless you can read the schematic.you need to follow the trace to the on off switch and check for voltages.

one other place to check is with the radio face towards you ,solder side up to you and left front of the board there is four pins in a row left to right.check the far left solder joint where the pin is at for voltage. when you turn on the radio if you still have voltage the trace to there is good .it will have to take it to the shop to have it repaired.you will be lucky if you find it.

sonoma · Post by **sonoma** » Saturday 3rd Mar 2012, 16:22

if you have voltage there check the 2nd pin from the left and see if you have power there, it is the feed to the rear of the radio.if you do not find anything someone else will need to look at it for you.

chrozell · Post by **chrozell** » Saturday 3rd Mar 2012, 16:33

I see 5 pins in a row on left side of board in the very corner and get 13.15 volt on the first 3 starting from left to right. Where can I get the voltage stabilizer and other parts? Only 4 pin I see has no voltage but not sure if they are what you are talking about.

sonoma · Post by **sonoma** » Saturday 3rd Mar 2012, 16:41

do you have voltages with the switch on and off.
1st pin should be hot in off. the other one should be hot when you turn it on both pins should be hot when on. if you feel like you can do it you can short the 2 pins together and see if the rear comes on..are you sure you have 13 volts with the radio on at the 1st pin ,if so sort the #1 AND#2 pins to see if on..what is confusing is the #1 pins feeds the switch and the 2nd pins is fed after the switch is turned on.

chrozell · Post by **chrozell** » Saturday 3rd Mar 2012, 16:56

yep like you said no1 has power off and both 1and 2 have power when on. Tried touching 1 to 2 but nothing happened. Where can I buy the voltage stabilizer?

sonoma · Post by **sonoma** » Saturday 3rd Mar 2012, 17:04

any cb shop will have them or RFparts .com.. the 2nd pin is after the switch is turned on .thats what is hard to understand that you do not have power at the switch when you turn on the radio but you do at the board.all the 2 pins you checked and jumpered is just before the switch then after you turn the switch on.

chrozell · Post by **chrozell** » Saturday 3rd Mar 2012, 17:25

Gotta go to work by midnite. Work 37 hours on weekends then have 5 days off. Thanks for all the help. Did not check for power at the switch itself when doing the pins. Will check when I can and get back.

sonoma · Post by **sonoma** » Saturday 3rd Mar 2012, 17:50

here is a link to the info on the radio.has all the specs on it.
the guy I had on the phone has 40 plus years of working on radios.that is all he does daily for a living and he can not explain all to check since it would be to in depth for you.
if you change the 827 put a 2sb817 in place it is a upgrade for the 827.with power on the 827 should have 13 volts on the rear leg and about 8 volts on the center and 13 volts on the front leg.this is with the controls facing you with the power switch on.

http://www.cbtricks.com/radios/galaxy/index.htm

sonoma · Post by **sonoma** » Saturday 3rd Mar 2012, 17:53

also do the lights come on the front of the radio when you turn it on.never did get that from you.

maybe someone else will see this post and respond also. to help.

chrozell · Post by **chrozell** » Saturday 3rd Mar 2012, 18:23

At work, the lights do not come on. Hope I can fix it, have the upgrade coming in a week for the q54 upgrade. Will try to diagnose and get it working again. Also had a 2 meter radio radio on and it is not reliable.

sonoma · Post by **sonoma** » Sunday 4th Mar 2012, 5:22

did you check all 3 legs of the 827 and see if there is voltage on all 3 with the power switch turned on and what do you have with the switch turned off.

make sure you have the dimmer switch turned all the way up to verify the lights are working.

chrozell · Post by **chrozell** » Sunday 4th Mar 2012, 6:49

I checked voltage on q54 and the left leg had 13.3 volts, the center has 9.4, and the right leg has no volts. I did make sure the lights switch was on anfd turned up. I ordered both the q54 and q55 and already replaced the finals. Will be a week before getting the parts and hopefully get it working good again. What else should I check?

sonoma · Post by **sonoma** » Sunday 4th Mar 2012, 7:26

you are saying voltages left and right.do not know what position you are holding the radio, that is why I said put the knobs towards you and tell my from front to the rear of the radio.voltages with the radio on and voltages with the radio off.I am wondering if you are getting voltage back to Q54 with the switch on.

does the freq counter come on ?

sonoma · Post by **sonoma** » Sunday 4th Mar 2012, 7:36

also why did you change the finals to irf520's?
did this radio come with the 520's?
what mod did you do to the radio in the 1st place?
what was wrong with it for you to be working on it.
did the radio work after you changed the finals or did you change them after the power shortage
thinking that could fix it.
what transistors did it have in it in the 1st place.
was the radio working before you opened it up to do what ever you wanted to do?

this is some of the info I need to help you'

sonoma · Post by **sonoma** » Sunday 4th Mar 2012, 7:56

I sent you a pm

chrozell · Post by **chrozell** » Sunday 4th Mar 2012, 8:13

I tried to use my phone at work and just l ost 15 minutes post I started. Will wait and use the pc.

sonoma · Post by **sonoma** » Sunday 4th Mar 2012, 8:24

be sure and check your PM

sonoma · Post by **sonoma** » Sunday 4th Mar 2012, 8:29

I keep losing post here also.write one up submit it and it never shows up.

I pulled my radio out of the truck and checked voltages this is with the radio knobs facing you.

power switch turned off
rear leg 13.33 volts
center leg 0 volts
front leg 13.33 volts

power switch on
rear leg 13.33 volts
center leg 4.79 volts
front leg 13.33 volts

this is the way yours should be.
if not change the q54 and see what happens

chrozell · Post by **chrozell** » Sunday 4th Mar 2012, 9:22

Yea mine has 13.4 volts on the front leg, and 9.3 on the center leg aebacklegwiththe power on. I er change out q54 &

55.

chrozell · Post by **chrozell** » Sunday 4th Mar 2012, 14:38

I bought the radio new a week ago and did the mods from defpom and it really had a great swing and power. I was messing with my new power supply a mega watt s-400 when I pulled a wire off my ps and it hit the 110 volt at the ps and there was a spark and sound like a fire cracker, I had the radio powered on and also a 2 meter Icom radio. That's when I changed the finals which were initially irf520's and replaced with the same. The radio had no problems before the power supply short then would not do anything. No lights,sound. Only 13.4 volts on the left leg of the q54, 9.4 volts on the center leg and 0 volts on the right leg closest to rear of radio with power on. I still have the mod for q54 and q55 and also the receive and noise blanker mod to do, waiting for parts. The 2 meter radio no longer works either. Funny the fuse on the galaxy did not blow, a 4 amp, but took out my radio. I just have to much luck! What else could I check?

sonoma · Post by **sonoma** » Sunday 4th Mar 2012, 15:06

what mod did you do from the sight?

the fuse only blows with amps and not voltage. which wire hit the 120 volts. ground or positive.
I would not mess with the tr17 mod and diodes unless you just want to try it.it is over rated as to what it does.
I have done dozens of the receive mods and did not see a gain as is stated. some people agree and disagree.each his own.
I would wait until you change Q54 and Q55 to see what it does.
did you read the PM I sent you?

chrozell · Post by **chrozell** » Sunday 4th Mar 2012, 15:53

Dont know how to get to the PM. The negative DC must have hit positive on 110. It really cracked and thought I just blew the finals. Believe your right will wait for the q54,q55 and they are my best bet. The diodes I want to do just to learn and play but after getting the radio back up and running correctly. Work till 8pm Sunday and can respond then. Not good at using my phone. Thanks for the help.

chrozell · Post by **chrozell** » Sunday 4th Mar 2012, 16:08

I did the swing mod then got this modulator off ebay and your mod had a better swing but left it alone. Did the extra channel mod and that worked great using 2 switches. My sideband sounded clear and strong and was really happy with my work. Believe it is the q55, get only volts at center leg now. Noticed the RX/TX light is on when powering up the radio but nothing else and tried the dimmer switch. Also have no sound or swing. Hope I can get it up and running.

sonoma · Post by **sonoma** » Sunday 4th Mar 2012, 16:13

at the left top of the page below where it says radio mods there is a bar that says
user control panel(new messages) view your post.

just click on new messages it will open that link up.it stands for personal messages

sonoma · Post by **sonoma** » Monday 5th Mar 2012, 11:05

chrozell wrote:I did the swing mod then got this modulator off ebay and your mod had a better swing but left it alone. Did the extra channel mod and that worked great using 2 switches. My sideband sounded clear and strong and was really happy with my work. Believe it is the q55, get only volts at center leg now. Noticed the RX/TX light is on when powering up the radio but nothing else and tried the dimmer switch. Also have no sound or swing. Hope I can get it up and running.

stay away from the so called modulator.if anything is in it is just a diode and resistor. that is worth 10 cents..some put a wire on to hook to 12 volts and I have cut 2 open to see what was there and the wire was just a dummy wire to make you think it did something.
not hooked to anything inside.
did you do the diode to I believe the r264 resistor?

chrozell · Post by **chrozell** » Monday 5th Mar 2012, 11:18

I will need to replace the r264, not enough on one end to solder to. The modulator made a noticeable decrease in the swing.

sonoma · Post by **sonoma** » Monday 5th Mar 2012, 15:12

did you figure out how to get you PM?

chrozell · Post by **chrozell** » Monday 5th Mar 2012, 15:19

Yes, thanks. But registered then have waited all day for them to ok my registration. They said they would send me an email when it was ok'd. Tried to login and it stated I had to wait for the registration to clear.

sonoma · Post by **sonoma** » Tuesday 6th Mar 2012, 4:30

there is another transistor that can go out and cause problems right with Q54 and Q55 .it is Q53 a 2sc945p. it is a small trans.it is located to the left of Q55 looking at the component side of the board with the knobs facing you. if it is blown and you put Q54 and Q55 in it can blow Q55 upon power up. they are very cheap and would be safe to change it also.
if you have a transistor tester you can pull it out and check it.in fact if you have one test the other 2 q54 and q55 now and see if the show blown.

if you do not have one let me know and send me a pm with your address and I will put one in the mail to you.

chrozell · Post by **chrozell** » Tuesday 6th Mar 2012, 6:48

I found q53 and will check it out. I just pulled up on utube this morning how to check transistors and it's easy. Ordered parts from Japan and waiting another week for them to get here to replace q55,q54, will replace q53 soon. Will the q53 blow if q55 is bad? There's a A1869 transistor screwed to the same side as q54 but close to the middle with 3 legs, could that be a problem and what is it?

sonoma · Post by **sonoma** » Tuesday 6th Mar 2012, 9:31

I believe it is a voltage regulator.if you will go to cb tricks and pull up the pitorials and the manuals section you can look all of that up.you do not have to have a logon for this section.only a logon for the forum.there is pictures of the board with all the location numbers. a parts list of all the components. schematics.complete service manuals .
Bennie has about all the info for galaxy's on his sight.
also between them is the audio amp about 10 legs

just go to radio infor on the left side of the screen and click on g for galaxy then galaxy and you will more info than you can absorb.