|
|
Joined:
January 2023
Posts: 3
| Hi All ..
I've got a issue with my Deacon. After a few minutes of playing it starts to cut out. Especially when applying any type of attack to the strings. Sounds almost like static. It happens with any setting on volume, tone or toggles. It also happens regardless of cable or amp. If I unplug the cable from the output jack and reinsert it into the guitar everything works perfectly for a minute or two...but eventually returns to a floppy. Static sound. I replaced the batteries. Anyone have an idea as what this could be? Or how I could proceed in doing PD.
Thanks |
|
| |
|
Joined:
October 2005
Posts: 4043
Location: Utah | That sounds like a voltage problem. Do you have electronics experience? I would start by tracing the power through the circuit. My guess would be a bad capacitor or possibly a resistor.
The battery is connected to the circuit when a cable is plugged into the jack. You could check the contacts on that jack for dirt and if the contacts are properly touching each other. I doubt this is the problem since the electronics work for a few minutes before failing, but it is a simple thing to check. |
|
| |
|
Joined:
February 2016
Posts: 1801
Location: When?? | Something to do with temperature, perhaps? Since it works well momentarily it may be something that takes a minute or two once the circuit is powered to warm to the point of malfunction, then cools rapidly when powered down. The 'roller coaster' effect. Like FlySig said, a capacitor or resistor can react that way to warming when they are shorted or otherwise corrupted. Dirty electronic components and solder connections can cause heat-up problems as well since the grime will hold onto the heat when under power. My first step would be to make sure everything is clean. I've had good luck using MAF sensor cleaner that is designed for and gentle on micro electronics to cut through heat-holding crud. CRC is a good brand for that. |
|
| |
|
Joined:
July 2019
Posts: 106
Location: northern Georgia | No guarantees, but I have had good results repairing old hifi electronics just by heating up the solder joints on board traces and wire interconnects to the circuit boards. This worked on a Yamaha graphic equalizer from the early 80s and an Onkyo preamp from the early 90s. In both cases, I had intermittent sound from the devices while under use, after the joints were heated, they are working like new. First I tried just cleaning connections with DeOxit. My second option was what I described, heating up the solder joints just until the solder melted with a 25 W iron. If that had not worked, I would have gotten a spraycan cooler and use it to cool specific resistors while the device was in use, to see if things change when it is cooled. If so, the resistor is likely bad. Old electrolytic capacitors can dry out and become defective, but that is usually in cases where they deal with higher current loads and get hot . For a preamp circuit like in your Deacon, running off a 9V battery, that should not occur. You could also try the spray cooler on transistors and opamps as well. |
|
| |
|
Joined:
July 2023
Posts: 3
Location: Virginia, USA | I agree with the previous responses. The circuit board in your guitar is almost 50 years old. It could be a cold solder joint, leaking electrolytic capacitor, or dirty contacts on the input jack. I had my Breadwinner in the shop last month to correct some playability issues. The tech who worked on it had experience with Ovation electric guitars and after correcting my problem noticed that the guitar's sound/tone wasn't right. Upon inspecting my circuit board he found three leaking caps. Now my tone is much improved. If you don't feel comfortable troubleshooting circuit boards, and the above responses don't fix the problem, see if you can find a guitar tech in your area knowledgeable and experienced with electronics.
Edited by Carbon 2023-09-28 9:31 PM
|
|
| |
|
Joined:
January 2006
Posts: 1118
Location: NW Washington State | I've fixed a few of these.
There could be a problem with the power switch that's built into the output jack. IIRC this is not like the stereo jack that's commonly used, instead there are little contacts in there.
Be careful when soldering or touching up solder joints, too much heat will cause the circuit traces on these boards to lift.
Cleaning the pots is good, don't use too much spray. I like to use a bit of a plain cleaner like CRC contact cleaner, followed by a cleaner/lube for pots like MG Nutrol or Faderlube. Remember that there are two little pots on the board that can be cleaned. You might clear up a switch problem by dripping a little bit of MG Super Contact Cleaner or Deoxit down the switch handle into a switch- doesn't always work.
Replacing the electrolytic caps is reasonable after all these years. There might be one or two in the signal path that could be replaced by film caps if they will fit.
Some extra shielding in the control cavity and pickguard won't hurt. The interstage transformer and/or the notch filter inductor can pick up 60 Hz hum- hard to block without a lot of heavy magnetic shielding.
Here's link to a thread with BruDev's schematics for the preamps- note the different versions. http://www.ovationfanclub.com/megabbs/forums/thread-view.asp?tid=32... BruDev is the master regarding these preamps but hasn't posted lately.
-Steve W.
Edited by numbfingers 2023-09-30 12:03 PM
|
|
| |
Deacon electronics....cuts out after a few minutes
