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Bill45
Junior Member
Username: Bill45
Post Number: 15
Registered: 7-2005
| | Posted on Saturday, July 15, 2006 - 3:57 pm: | 
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Meter Lights Dimming on a Galaxy DX 2517!
I developed a weird problem with my 2517 lately. It has a Ranger Board #EPT690010C, When I key up on AM both meter lights look normal until I put some mod. to it then they dim and get normal again according to the pitch of my voice. Not too bad, reports say it sounds the same. Now when I put it on SSB and key it up it looks good, but now when I put mod. to it both of the meters just about go out, they also flicker according to my voice. Everybody says that it sounds good to them. I'm thinking (that's dangerous) that if the lights take something like 8 volts or so and they are dropping, other things that run on 8 volts should be dropping also. This is a good one to put a Magnum S9 into, and with all of the extra room I could put a 150 watt kicker in there also! I'm using a Realistic TRC-458 for now: AM-5w and SSB, PEP about 35watts. It has better ears than the 2517 also, I've had this radio since 1978 and found it in the attic. For some reason when I key up the whole city finds me and gets on me saying that I'm running a kicker and I'm not but I am running a stock microphone! If anybody can help me with the lights on the 2517 I would be very HAPPY :-) |
Hollowpoint445
Senior Member
Username: Hollowpoint445
Post Number: 1302
Registered: 6-2004
| | Posted on Saturday, July 15, 2006 - 10:12 pm: |
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The radio has been peaked beyond the current capacity of the power supply. Connect it to a big external supply if you can. The lights will probably look fine then.
If that is the case, I really doubt that it sounds good when that happens. On SSB there should be a considerable warble in your audio during voice peaks. |
Bill45
Junior Member
Username: Bill45
Post Number: 16
Registered: 7-2005
| | Posted on Sunday, July 16, 2006 - 10:53 am: |
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Hi Hollowpoint445,
I think that you are going in the wrong direction. AM: my low power is set to 1 watt and high is set to 10 watts. SSB when on a dummy load and a watt meter, set to PEP and when I key up and put some mod in it , the meter only shows about 35 watts. Now if I put a high whistle in it the meter might go to 45 watts. I also tried leaving a volt meter on the power supply, the volts are set to 13.8 volts and when I do all of the tests it stays at 13.8 volts. I tend to think that it is comming from the Q37 "2SA473" voltage regulator, or one of the diodes near it. It's so tight in there. Sorry to put you down on the over peak, if anything it is under peaked. I have another set near it without an antenna on it and when I key the 2517 up is sounds OK on the other radio! I'm going to have to put some more time in the area of the Q37. Either that transistor is opened or one of the diodes there opened on me. What do you think?
Thanks, 73s |
Hollowpoint445
Senior Member
Username: Hollowpoint445
Post Number: 1304
Registered: 6-2004
| | Posted on Sunday, July 16, 2006 - 12:27 pm: |
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First, let me say that I don't currently nor have ever owned, used, or even looked at a Galaxy base radio because I prefer Uniden double conversion SSB radios. My thinking is why have an imitation when you can own the original?
In my experience with radios I've used and heard on the air, it is usually the case the the lights dim when they are peaked to the point where the power supply cannot meet the current demands of the radio on voice peaks - which is exactly the problem that you seem to be having. I say seem to be having because I don't know how the lamps are powered in your radio. What voltage do the lamps operate? What does it drop to when they dim? Most base units have lamps that operate on 13.8V from the power supply. You mention that your radio's power supply stays right at 13.8 volts even when the lamps dim. As I'm not familiar with the radio, I can't tell you where to measure the voltage exactly, but it would be right where the connection is made to the main board, and not at the power supply itself. If the voltage is different at the lamps than at the power supply connection to the board then you'll have to investigate where and how the lamps are powered, and then find out why they are dimming on voice peaks. My suspicion is still that the power supply cannot meet the current demands, which is why I suggested powering it from an external power supply that is easily capable of twice the current demand of the radio under full modulation.
BTW - Your radio is not under peaked if it uses the standard dual 2312 finals of most Galaxy radios. If anything it is over peaked unless your meters are generous. You'll never actually see more than 40 watts out of the back of one of these radios at 13.8 volts with a decent meter, just as you'll never see more than 20 watts out of a Uniden SSB rig that uses a 1969 final - which would be an amazing accomplishment for a few seconds until the final transistor burnt up. |
Bill45
Junior Member
Username: Bill45
Post Number: 17
Registered: 7-2005
| | Posted on Sunday, July 16, 2006 - 3:08 pm: |
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Hi Again Hollowpoint445,I really appreciate your help. As you stated about Uniden I'll go along with you 100%, This Galaxy is going to be my last one! It does have 2312 for finals. What gets me is that this happened all at once on it's own, the cover hasn't been off of it for at least 8 months I'd say, because everything was working fine with it. When this happened I purchased a Service and Owners Manual thru rfparts.com, a good one with only what you are looking for, not a photo copy from Sams. I followed the path for these lights on the circuit diagram and they both lead to a 8VDC regulator #2SA473 from there they travel a +8V Bus to another 8V regulator #2SA1282 then 1 RX and 1 TX Voltage switches, and on and on. This tells me that these lights run on 8 DC Volts. For now the rig is at the bottom of a Realistic TRC-458 and some Workman Meters. I can't afford to buy a BIRD meter for what I do. I would take that money and buy a Uniden! Like I stated above it happened by itself, the channel readout and the frequency counter are OK they don't dim at all. I got so mad at this Galaxy from the testing the other day, that is why it's at the bottom of the stack! I'm going to have to dig it out again and test some voltages, from what this book says is that the 2SA437 B=13.00, C=8.65, E=13.66 all VDC, I'll also check the voltages of some other things also, honestly when I look at the 2517 I get sick! Can I ask you which Uniden do you run? I also have a 40 Amp Continuous/ Variable Voltage, 5-15VDC Power Supply from Diamond Antenna, plenty of power but I'm not going that route with the Galaxy.
Thanks, 73s |
Hollowpoint445
Senior Member
Username: Hollowpoint445
Post Number: 1305
Registered: 6-2004
| | Posted on Sunday, July 16, 2006 - 6:18 pm: |
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You've got a Uniden board in your TRC458! It's similar to the board in my Courier Centurion 40D. Pretty nice radios. I'd say they're only slightly behind the 8719 dual conversion Uniden SSB radios (148/2000/Grant/Madison) in performance. Close enough that the board with the better alignment would be the better performer.
I also have a TRC490 which is an 8734 single conversion SSB board similar to an 8719 Washington. It's also very good on SSB, but not that good on AM. I'm talking about the receivers here, because the transmitters on these radios are basically the same design and a watt here or there doesn't make any difference to me. I don't "peak" my radios because I don't feel it's worth it. |
Bill45
Junior Member
Username: Bill45
Post Number: 18
Registered: 7-2005
| | Posted on Monday, July 17, 2006 - 9:38 am: |
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Hi Hollowpoint445, The TRC458 that I have puts out 4 watts on AM, and on SSB I never checked, all I know is that it works. That is all that matters to me. On the 2517 I get back to you after I do "some" voltage checks. If I can't get it I'm going to pack it up and send it off to my Tec. Mike's Electronics in Frankfort, Ohio. Galaxy radios are his specials. I'm going to have him go over the whole radio for alignments in both TX and RX. He really is a good guy and does good work. Everyone else that I know that uses him says the same thing. He already new that I was going to send it to him for the other work, but he don't know about the light problem. I also read on the forum someplace that Galaxy 2517 is having problems with power supply failure and they are replacing TR606 with a 2SD2531 as they come into the shop for any type of repairs. I'll keep in touch with you and let you know how things turn out for me with the 2517. Thanks for all of your help!
Bill45 73s |
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