Phonoland

I have a problem that i have never seen on a Rowe from the 1980's. Intermittenly, and becoming more frequently.... it will mute the amp at the end of the record and will not reject. I have tested the reject switch while a record is playing and the same result... Amp mutes while I hold the button, either button the one user one or the cancel switch on the mech and wont reject and I release the button and it continues to play, till the end and then it mutes and just keeps spinning and the tone arm does not go back to home position and the record continues to spin. Seems if I power cycle the box it will reset the issue and the tone arm goes home and record is returned to carriage. Any ideas? I looked in the service manual for this under the troubleshooting guide and did not have this issue listed.

I don't recall ever seeing that happen, on a Rowe--I would look at the motor LED on the MCC--is it lighting when you mute it--If so, but the motor is not running, is the motor being powered---by chance, is the armature stuck "inside" the gear box--if so--OIL it wit 20wt. ND oil, on both ends of the armature--then FILL the large felt wicks on both ends --
That may solve your problem ?? Ron Rich

Check the cam switches, mechanism control (for dry joints/cold joints USA on the connection pins).
You are loosing 28 volts DC, there could be an issue on the Power Supply PCB or it could be down to a faulty service switch.

Regards
Alan

Alan Hood
ami-man
UK

Ron Rich wrote:I don't recall ever seeing that happen, on a Rowe--I would look at the motor LED on the MCC--is it lighting when you mute it--If so, but the motor is not running, is the motor being powered---by chance, is the armature stuck "inside" the gear box--if so--OIL it wit 20wt. ND oil, on both ends of the armature--then FILL the large felt wicks on both ends --
That may solve your problem ?? Ron Rich

Hi Ron good to hear from you. It is lighting along with the Cancel LED when I hit the cancel switch. it mutes the amp but does not engage. I have noticed that the +28vdc led on power supply is not lighting, nor does it light when I remove the mech connections. maybe a bad power supply???

ami-man wrote:Check the cam switches, mechanism control (for dry joints/cold joints USA on the connection pins).
You are loosing 28 volts DC, there could be an issue on the Power Supply PCB or it could be down to a faulty service switch.

Regards
Alan

Alan Hood
ami-man
UK

Thank you Alan. I have noticed that the +28VDC led is out on the power supply and per the maunal it should light when I remove the mech plug and it does not.

Remove the Power supply from the jukebox and by removing the four 1/4AF 4BA machine screws that hold in place the PCB remove the board.
On there is two four pin connections to the two transistors and a long plug from the transformer, remove all of the plugs and look at the header pins for the long connectior for any dry joints (cold joints USA) if there are any then reflow the soldered joints.

Look at the diodes and test them for the 28 volt DC circuit if any are bad replace them, if any were bad then one of the fuses on the board will have blown.

Please let us know how you get on.

Regards
Alan

Alan Hood
ami-man
UK

You could be "loosing" that power supply, intermittently--check the plugs/headers as Alan suggested--but I wonder --could the LED be burned out--I think I would meter this--? Ron Rich

Ron Rich wrote:You could be "loosing" that power supply, intermittently--check the plugs/headers as Alan suggested--but I wonder --could the LED be burned out--I think I would meter this--? Ron Rich

Ok I found the problem now. its the Mech control board. I did as Alan suggested and there were some questionable solder joints on the ps borad so I resoldered them and it worked. Well it worked 3 times then started the same stuff. but I noticed it would reject after hitting the cancel button on the mech multiple times then the mech started intermittlently running, so applying some pressure on the connections on the mech control, it started working again. so I grabbed a good one I had and works like a charm. I am now in the process of soldering the pins on the known bad board. Thanks guys, it sure does help running these issues to others.

Robert

Ok resoldered every pin on the mech control and cleaned the board. ( looks like somehting was spilled ) and works like a champ. Thanks again Alan and Ron for your assistance.

Robert

Robert,
Glad you got it-- One thing to remember when dealing with this type plug/socket--"Someone" in their inanimate wisdom designed the header pins to be round, and designed the pins square --this is a "no-no", which they finally found out and redesigned the headers square.
HOWEVER, the pins used in the plugs are , IMHO, too soft, and loose tension. A partial cure for this is to remove the pins, one at a time from the plug, clean, reform, re-insert them-- Ron Rich