Conn 652 Restoration- Help needed!

[Yaeld85]

Hello!

I got a nice Conn 652 Theatre Organ, but some functions aren't working correctly.
My English is really bad because I am not a native speaker of English, but I hope you understand what I want to say and can help me with some tips how to fix the organ.

Here are the (bigger) problems:
1. All Tuned Percussions sound like a cracking noise. If Repeat is activated, the cracking noise repeats at that rate.
2. On the Solo-Manual the Reed-Voices aren't sounding at all. The Tibias are working.
3. On the Great-Manual the Reed-Voices are just sounding on the lowest octave. The Transposer will move those sounding notes up or down. The 16' Coupler will move those sounding notes to the next octave (one octave higher), so the two lowest to octaves are sounding.

What are the causes for the issues? What do I need to check (I am familiar with using the Voltmeter)?

[tucsondave]

You must be careful when working on these organs so you don't cause damage from static electricity.

Usually the cause is bad solder connections on the white plugs.
Re-solder the plug pins on the bottom of the boards.
Start with the boards that have small boards plugged into them. But you may have to do all the boards.
Do one board at a time then test the organ.
If you have a service manual you should check the power supply voltages.

If you just got the organ then also check for rodent damage inside.

td

[Guest]

This is the message:

Hello, I have a Conn 652 organ and would very much like to change out the spring reverb to a digital reverb but don't know how make the install. I have already purchased a DPS Ambience Processor/digital reverb with RCA connections. I would very much appreciate any help with instructions of how to install the digital reverb. Thanks.

Barry

[greenfox4075]

Hello,

I don't have any suggestion for the cracking noise in the tuned percussions

The other symptoms you mention I would say are all related to the LSI Keyer cards. These cards are small vertical circuit boards. Each manual has a section of Tibia and Orchestral. Each card controls an octave in reverse order to the actual keyboard. Take anti static precautions then you can move the cards to get function where it suits best while repairing the others to get full function.

It sounds to me like someone has already been poking around with these cards. You may find some missing or unplugged.
In my experience when a card fails it causes a noise playing all the notes on a manual. Unplugging one card at a time will find the culprit.
Once you find which are working, you can position them to give most useful function.
As has been mentioned, the solder joints can be a problem, so you should remelt every joint in the system.
These LSI keyer IC's are still available. When replacing I would suggest installing an IC socket to suit.