I've put it back together. Tried to turn it on. Dim bulb goes on about 50% brightness then relays try switch and the DB goes to 100% brightness, relay tries to click again and goes down to 50%. Keeps repeating that cycle, no lights come on the front panel.
I'm thinking I've missed something. Hoping it's not the wire connectors, they are all loose. Had to solder one of a three pin wires directly to the joint as it came off as I gently pulled it out.
It came on last time. I've still not complely finished the rectifier joint. May of had a knock again.
Will it not fire up because of something not right on the channel I've had out or could it be a power supply issue?
I will try sort the rectifier out later yet won't mind waiting till the New Year when I get some more test equipment.
I'm thinking I've missed something. Hoping it's not the wire connectors, they are all loose. Had to solder one of a three pin wires directly to the joint as it came off as I gently pulled it out.
It came on last time. I've still not complely finished the rectifier joint. May of had a knock again.
Will it not fire up because of something not right on the channel I've had out or could it be a power supply issue?
I will try sort the rectifier out later yet won't mind waiting till the New Year when I get some more test equipment.
I found my PV-1.3k would not operate on a 100 W bulb in the AC line. I had to use a 1200 W room heater heating element in the AC line. Without that it would launch steel transistor tops to the ceiling. Some of those transistors that passed the double diode test had been overstressed by the output short. Cold resistance of the heater was 6.2 ohms, but don't take that literally. Our AC source is 120 vac, half of yours.
Reference the Q205, yes, crackling went away when I washed off the ink bridging many traces. Suppose it had some carbon in it. Those traces were for the LED volume indicator, so nothing nice about those current. Reason for graphic equalizer in PA, the mikes will howl from feedback if not well separated from speakers. Besides, this organ has a whistle which was masked in the original speakers by lack of high freq response. Those allen drivers had foam surrounds that deteriorated after 25 years, had to be scrapped. Using KLH23 hi fi speakers for the organ, now for the minister's speech mixed in. Graphic equalizer will take the whistle out without causing too much high freq suppression that a regular treble cut in the mixer is doing. Modern mixers have a software howl supression built in, not buying one of those when I can get used stuff from Mississippi.
Reference the Q205, yes, crackling went away when I washed off the ink bridging many traces. Suppose it had some carbon in it. Those traces were for the LED volume indicator, so nothing nice about those current. Reason for graphic equalizer in PA, the mikes will howl from feedback if not well separated from speakers. Besides, this organ has a whistle which was masked in the original speakers by lack of high freq response. Those allen drivers had foam surrounds that deteriorated after 25 years, had to be scrapped. Using KLH23 hi fi speakers for the organ, now for the minister's speech mixed in. Graphic equalizer will take the whistle out without causing too much high freq suppression that a regular treble cut in the mixer is doing. Modern mixers have a software howl supression built in, not buying one of those when I can get used stuff from Mississippi.
Last edited:
Very interesting. I like your information a lot. The only techs I have near me don't really give any advice, probably because they both always drunk on spirits and tend to bodge their work. So I'm guessing the GE is set with the HF flatter or below 0? And doing this ruduces microphone feedback.
I just had another look on the Peavy. Unplug the channel I've worked on and powered it back up, DB was much less brighter, lights come on the front panel and remaining relays clicked. The little leds on the channel I worked on are on, relay is still noisy, not sure if that's because it's unplugged or faulty still as I thought last time.
Im not comfortable with the metal backed transistors on each side of the heatsink being insulated or not, I'll look up for their spec sheet to make sure. I thought all emitters backed transistors didn't require insulation yet one Cxxx was insulated and the Axxx wasn't (unless I misplaced it and never noticed in the first place).
I will look into a element to use for the New Year.
I just had another look on the Peavy. Unplug the channel I've worked on and powered it back up, DB was much less brighter, lights come on the front panel and remaining relays clicked. The little leds on the channel I worked on are on, relay is still noisy, not sure if that's because it's unplugged or faulty still as I thought last time.
Im not comfortable with the metal backed transistors on each side of the heatsink being insulated or not, I'll look up for their spec sheet to make sure. I thought all emitters backed transistors didn't require insulation yet one Cxxx was insulated and the Axxx wasn't (unless I misplaced it and never noticed in the first place).
I will look into a element to use for the New Year.
Peavey CS800x and Peavey PV-1.3k have output transistor collectors common. So if the heat sink they are mounted on is insulated from the case (ground) then the output transistors can live without insulators. My PV-1.3k had insulators on the output transistors.
At church I have the mixer treble turned down on the organ input, which kills the sound some. With a graphic equalizer I can turn down only the band of the whistle, and leave the other high frequencies flat. Same with the mike howl problem. The frequency the howl occurs at has to do with the dimension of the reflective path in the room. turning down only that band on a 10 or 12 band equalizer allows more high frequencies to get through in other bands.
I never had a working tech tell me much, except for the guys at the next bench when I was a tech. I learned from books, from a former Navy radio repairman in high school, my chemistry teacher. Now we have forums, which is cool. If I go to a bar the talk is cards & cats (sports teams), nothing I'm interested in. I do my own sport, non-competitive bike riding. Nobody is interested in my stories about those. I type faster than anybody talks so forums are cool.
At church I have the mixer treble turned down on the organ input, which kills the sound some. With a graphic equalizer I can turn down only the band of the whistle, and leave the other high frequencies flat. Same with the mike howl problem. The frequency the howl occurs at has to do with the dimension of the reflective path in the room. turning down only that band on a 10 or 12 band equalizer allows more high frequencies to get through in other bands.
I never had a working tech tell me much, except for the guys at the next bench when I was a tech. I learned from books, from a former Navy radio repairman in high school, my chemistry teacher. Now we have forums, which is cool. If I go to a bar the talk is cards & cats (sports teams), nothing I'm interested in. I do my own sport, non-competitive bike riding. Nobody is interested in my stories about those. I type faster than anybody talks so forums are cool.
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.