Rockola 425 nterlock Relay

Im having problems getting the trip coil to release on my interlock relay in my Rockola 425. After the record is placed on the platter the selector lever cancel solenoid turns on but never turns off unless I do it manually. The release coil seems to work properly but the trip coil stays energized and keeps putting current through the solenoids. It happens with both a and b side solenoids. It seems there must be some switch somewhere that turns off the trip coil but I've not been able to find it. I cant find anything wrong in the interlock relay so Im wondering if its somewhere else.

I am not quite sure about what you have written--Do you have the service manual for that phono ? There should be a"flow chart"showing you exactly what should happen, when. I don't know how the "interlock relay" relates to what I think you are talking about--the "Pin cancel ("hammer") coils". NOTE: IF fused ( not CB'ed), be sure fuse size is not larger then posted on chassis !! Those coils DO, burn out, easily ! Ron Rich

Hi
I would take a look at micro switches two and three, number 3 especially as it connects back to the interlock relay relaxing it after the record has been placed on the turntable and the selection lever has been reset. Although it controls the braking of the gripper motor which would run on if the switch was faulty, could be an intermittent switch or loose plug connection. No harm to clean the wobble plate slip rings as well
clones

Thanks for your quick responses. I do have the service manual, though I've had a tough time going through it. The interlock relay is in the control box just underneath the record platter. When I push down on the micro switch it does release the trip coil but doesn't disconnect the power. As soon as I let go it re-energizes the trip coil. Im beginning to wonder if maybe its been wired in a strange way. The lockbar is always energized and I've noticed that the checkoff motor cam does'nt seem to do anything. Also the contacts for the deselection switches (I think its called the Play Control Relay) don't seem to have any current. Maybe the previous owner in wiring it to never need coins disconnected the deselection circuit? Does that make sense?

Hi
If set for free play the lockbar will be energised the whole time, if you look at the ratckets on the credit unit the spring and pawl may have been removed. This pawl cancels a credit via the ratchets. The play control relay energises when a selection is made or if you use the scan lever to cycle the magazine. The micro switches are supposed to operate in sequence, probably best to turn off machine and cycle the gripper back manually to home position via the gripper motor until you can't turn it any further and check the adjustments of micro switches
clones

Thanks for the info. Its looking like the microswitches are the problem at this point. Though they seem to be adjusted properly for the cams and they click, a continuity test indicates problems with the switches. After I tried cleaning them it only got worse, so I've ordered a new set. The machine had oil all over it when I got it so I suspect over the years oil got into the switches when they oiled the cams. The bright side has been that the machine is starting to sound great. It was barely audible when I first got it. Now its booming.

Sounds as if you found it--"Oil" does tend to enter and contaminate MicroSwitches, and other open, and enclosed type, switches !
HINT: Don't know where you ordered them from, but prior to use, be sure to check them as pointed out in the post above--as even "new" ones, can be contaminated !! (and that's what called a "Bi--h", when new parts are installed that are BAD !--NOT !) Ron Rich

Well Im sorry to say that it wasn't the micro switches. I put them in and it cleared some other things up, notably minor problems with the write in side of things. But not the problem Im having. Im a bit stumped. There seems to be something that keeps the trip coil charged after the record has been placed and the hammer has deselected it. Im able to manually trip things with the magazine motor relay, but it just doesnt let go otherwise (unless I hold down the #2 micro switch but then it re energizes once I let go of it).

Is there another switch somewhere thats just not working? Again Im wondering if its something to do with being hard wired to be on all the time. I checked and rechecked the Interlock relay switches and cant find anything. Ive cleaned out the snap switches. At one point I thought it was the trip coil itself but it seems to work fine in other routines. Also Ive wondered if its the release coil but again other routines seem to work fine.

Could it possibly be my new solenoids? I bought about 6 from macro pinball. http://www.marcospecialties.com/control ... NG=rockola But of course the reason I bought them was that the the solenoids were burning out for this very reason.

Any help would greatly appreciated.

Hi
Sill think its something with micro switch 3. The solenoids look fine, are all the wires connected back in the right places at the microswitches. Maybe if you could post a few photos of the control box, microswitches and general cam area
Clones

Only thing I can say is, unless you like replacing these coils, get out the schematic, read it, and determine what, how, this coil is supposed to be powered--another suspicious thing is, why, is the fuse/circuit breaker not opening prior to the coil burning out ?? ( over sized fuse--jumped ???) Ron Rich

Just a stray thought here, but look at the drawing in the service manual showing the positions of the interlock in the control box at different sequences. Look at your interlock. On a couple of my machines, this was tripped in the wrong position. Manually tripping it with a non-conductor (very important!) tool restored function. This was always connected with trouble with Micro #3 functions. Another thing to check on the Micros: the manual tells you where to set the cam, but It’s not enough that #1 in in the notch with the bow over the magazine and gripper jaws retracted; #3 also has to drop into the notch with the needle on the record. There's one sweet spot where everything works.
Patrick

Great replies thanks. I will try all of them once I get back from vacation. Pretty much running out the door right now. One question. I saw that there is a selenium rectifier in the control box, its so old that I could only find it listed as an antique. It was in black plastic so I didnt recognize it as such. Im thinking this might be part of the problem. Any advice on how to replace it? From what I've gathered on the web, I can replace it with a 1n4004 or 1n4007 diode. Is this right and what resistor should I add to cut down the voltage?

Back from my trip.

Okay I've checked the cam and it seems to be properly adjusted. I tried manually switching the interlock relay and no go, it resets back to where it was. I looked at the micro switches and couldn't find anything that looked wrong.

What I did find though is that the magazine relay also is not letting go and keeps the interlock relay energized. Should this be released? When I trip it it releases the interlock relay. I can also get the solonoids to release by moving the interlock relay but it stays energized. Could the interlock trip coil be bad? The 60ohm resistor gets pretty hot and the coil does seem to have melted a bit. .

A little history, when I got the machine this problem seems to have been mitigated by the previous owner putting in a fuse above the rating. The solonoids heated up but the interlock relay would let go after awhile. Now it never lets go.

"HOW" did you "look at the MicroSwitches" ? See post above ( How to check--") if you just "looked" at them !
Did you check for relay magnetism ?

Ron Rich

They were brand new and I checked continuity before putting them in. So I just checked for mistakes on wiring. One thing that I just noticed when looking for parts is that the delay rings on my magazine motor relay are opposite how they appear here: https://www.jukebox-revival.eu/staging/ ... tches.html Could this be the problem? And how would I switch the delay rings. My delay rings are on the bottom. Could this be it possibly causing the magazine motor to hang on? How does one change this?