Rodgers C-445 organ problem

[CapLeaker]

Got a Rodgers C-445 digital church organ to repair and no, I didn't bring the whole thing home.

Complaint: No audio, heard a pop in the speakers and it smells like burnt electronics.

So I called Rodgers for a service manual. Those things are not to find on the net and neither will Rodgers sell you one, rather they send you to their dealer network. Frig, if I want a schematic or service manual, I surely don't want the dealer network, as the next dealer is like 300km from here. Pfft.

Checked the linear PSU and found that the -12V rail was almost 0V and the +12V rail only like 5V, plus the heat sink getting quite warm on the 12V regulator. I unplugged the ribbon cable that goes from the PSU to the 4 channel preamp (board number 5218-30). Ha! -12V came back and the +12 V too.

The damage on the 4 channel preamp board:

After talking out the board, I noticed there wasn't a short to GND, rather the -12V and the +12V where shorted. Fixed the hole in the circuit board and repaired the corroded traces of the leaking caplythic juice, replaced C27, C28, C1 and C3. So hopefully that does the trick tomorrow when I put it back in.

BTW: I replaced the 4 caps with Panasonic FM series.

[Andrew F. Ali]

Re: Rodgers C-445 organ problem

Good Luck...Keeping my fingers crossed for you...It'll work...I'm sure..

[CapLeaker]

Re: Rodgers C-445 organ problem

Here is a small follow up:
Went there and put the pre amplifier board back into its place, hooked up all the cables and she works like a charm.

Here is a picture of the whole preamplifier board before I took it out of the organ.

[ReeceyBurger123]

Re: Rodgers C-445 organ problem

Sweet work dont suppose you could do a video of the final project ?

[CapLeaker]

Re: Rodgers C-445 organ problem

Sweet work dont suppose you could do a video of the final project ?

Too late mate... The organ is already back together. This thing is big. I couldn't bring the whole thing home, so I just took the pre amplifier board and done the usual jazz, put it back together and everything is A1.

Basically you only have some key boards, a PSU, an digital audio processing board, a audio pre amplifier board, a audio amplifier and a couple other smaller boards. That's it. As long as the digital board is good, the rest shouldn't be a problem to fix.

A litte tip when you repair one: bring a stubby screwdriver. You gonna need it.

[brianpretty]

Re: Rodgers C-445 organ problem

Not sure if anyone follows this anymore, But I recently repaired the same unit, Only my issue was the lower capacitor, when it failed it took out R57 (10 ohm) current limiting resistor. So my fix was to swap new C27 and C28 Caps, Good to go again. See Pic.

[brianpretty]

Re: Rodgers C-445 organ problem

And Thanks to CapLeaker for the post, I could not see what the value of R57 was.

[CapLeaker]

Re: Rodgers C-445 organ problem

And Thanks to CapLeaker for the post, I could not see what the value of R57 was.

You're welcome. Glad the post helped you out and got your organ going again.!
I am still around, just been busy and that's going to be like that for a little while yet.

[brianpretty]

Re: Rodgers C-445 organ problem

Just put it all back together yesterday and good news, All's well. Organ is humming again. Some caps and a 10 ohm resistor later.

[CapLeaker]

Re: Rodgers C-445 organ problem

sweet!

[Jabberwocky_Music]

Re: Rodgers C-445 organ problem

And Thanks to CapLeaker for the post, I could not see what the value of R57 was.

And another thanks to CapLeaker for the post from me, another half a year later! Mine was actually working (this is my home practice organ), but I had a bizarre issue where certain combinations of notes played on one of the manuals would cause all of the notes to stop sounding on that division. So off to google I went, to see if it's a common problem on these. Finding nothing, I went less specific looking for any problems with these, and found this thread.

Since I had the thing open, I decided to look at the shape of the capacitors. Lo and behold, C27 has seen better days! I haven't gotten it off yet (I need to borrow a soldering iron, I don't do this stuff a lot!) so I don't know the shape of the board underneath yet. But it's not as bad as Brian's post! That resistor is toast, and the diode looks like it's bleached! Yikes!

[CapLeaker]

Re: Rodgers C-445 organ problem

The "white diode" is like that. It isn't bleached by getting hot or anything, it is white from factory. Look at my pictures.
Good luck fixing yours, maybe take some pictures and post them here using the Attachment function (Post Reply).
As I recall the original complaint, the organ worked fine until that cap C27 went south.

[stj]

Re: Rodgers C-445 organ problem

the white part is a link-wire

funny how a company supplies churches of all places and then tries to fuck them over when it needs repair!

[CapLeaker]

Re: Rodgers C-445 organ problem

the white part is a link-wire

funny how a company supplies churches of all places and then tries to fuck them over when it needs repair!

yes, it is just a jumper

[sparky61]

Re: Rodgers C-445 organ problem

Thanks for your notes on the C445 bad caps - it was the preamp board. One cap leaked, corroded the resistor lead (which overheated of course). Just got the parts - have to go back to the church and install/test.

[sparky61]

Re: Rodgers C-445 organ problem

The power supply caps all seemed good. +12v & -12v on spec

[CapLeaker]

Re: Rodgers C-445 organ problem

Yep, it's the 4 channel preamp board that's causing trouble. I fixed that thing 4 years ago and it hasn't come back yet. Good that you could fix yours with the help of this thread.

[Jabberwocky_Music]

Re: Rodgers C-445 organ problem

The "white diode" is like that. It isn't bleached by getting hot or anything, it is white from factory. Look at my pictures.
Good luck fixing yours, maybe take some pictures and post them here using the Attachment function (Post Reply).
As I recall the original complaint, the organ worked fine until that cap C27 went south.

So, as it turns out, my actual problem was unrelated to that capacitor business. I've decided to retire the instrument, and use the manuals, pedalboard, and stop controls/volume pedal to make a portable MIDI rig. I hate how it sounds anyway, and found myself using it as a MIDI controller 95% of the time, or more. My only worry was whether the magnetic reed switches for the pedalboard (which is an amazing inclusion given the budget nature of this model) were inside the console. Luckily, they're attached to a thin piece of board screwed to the front. So it'll be a bit of a project, but I'm determined to get it done. Worst case scenario, I fail at DIY, and buy some pre-made MIDI hardware from Poland. It's cheap enough there, and I have family who can ship it over for me if they charge too much for overseas.

Regarding the diode, I'm definitely no expert. The reason I commented on it is because mine looks nothing like that! I'm sure manufacturers might source different components if price or supply changes, but is it typical for a single diode like that on the same board? On mine, D7 and D8 look like the same part, so the blank white one stood out to me. It almost makes me wonder if someone replaced that diode because there was already a problem, but didn't do what you did (and, you know, diagnose the actual problem and fix that!).

Either way, sorry I don't check here often, but I'll try to remember to post some pictures tomorrow.

[Babeuh]

Re: Rodgers C-445 organ problem

Hi ,
According to the service manual, D7 and D8 are identical silicon diodes.
I guess they prevent the capacitor to discharge too rapidly when the power is switched off, to avoid a "plong'.
Replacing one by a wire may be an update to original schema.