Rowe CD 100-A only plays through Right Channel

[foxman]

Hello all,
I picked up a nice Rowe CD 100-A Juke box a month ago, it's a 1991 model. The unit was playing fine, and then out of the blue, it will only play out of the right channel. I fiddled around with the EQ, and diagnosed that the issue is not with the CD mech, as it will play out of the right channel when switching the left and right RCA inputs from the CD mech output. The first time this happened, I unplugged the power and plugged it back in, and the problem went away. Then the second time it happened the right channel went out. Same thing, unplugged and plugged back in, then both channels worked. Now I am back to the right channel only working.  ???I noticed the difference after turning the power back on and playing the juke box each of these times. I turned the power off, unplugged and plugged in multiple times, but no luck. When no songs are playing I get a very faint buzzing noise out of both right and left sides. I am wondering if I hurt something by adjusting the equalizers or moving it into the basement, it never lost a channel when playing in the garage. The puzzling thing for me is that at first it was intermittent, and unplugging solved it, now it lost the left channel completely. It appears that there is some sort of power going to the left because the faint buzzing matches the right side when no song is playing.
Any help would be appreciated on where to start,and what to look for. I was excited to have it ready to play during our holiday party in a few weeks!

[ami-man]

Hello Foxman,

Welcome to the forum, what is your name?

With regards to your amplifier problem, if you can solder, then check the the pre-amplifier and driver boards for dry joints (cold joints USA) on the connection pins that the molex plug connect to the boards, pay close attention to the jumper plug that is on the pre amp.

Regards
Alan

Alan Hood
ami-man
UK

[foxman]

Hi Alan,
Thanks for responding,
My name is Jeremy. I am a bit of a novice when it comes to soldering, but have done some minor work in the past. you can tell how novice I am because I will have to look up what "Dry joints" and "Cold joints" and "Molex Plug" are online. I plan on taking the plunge tonight and pulling the amplifier out to inspect it. It seems like a simple process of disconnecting the wire connections and power chord and removing the sceuring screw on the side where the amp hangs. The external speaker connections on the left side are all not giving me any output as well, just thought I'd add that in... I will post up what I find tonight in hopes that I've discovered why the unit dropped the left channel.

Any thoughts on why it dropped the left, was cured by a power disconnect,  then dropped the right, then fixed by a power disconnect,  then finally dropped the left again? I'm thinking the answer may be found by inspecting what you suggest in your reply..

Thanks for all the help!

[foxman]

So I disconnected and removed he Amp. I checked all connections and looked for burns and or missing solder, with no luck. I took a shop vac and vacuumed out the boards carefully and replace the amp. The first time I powered it up, there was no thump when plugging it in, and no sound when playing. I powered down, un plugged and plugged back in again, and the thump came back when plugging in. Played a song and only right channel. I decided to start wiggling wires and found the long thin wire bank with 3 loops of wire coming out of it when wiggled wold start to power the left channel. so I worked it in and out and the channel now plays good, both sides. I noticed he speakers were were from the E6 poles on the speaker connections so I switched those to the E7 poles like I have read is correct on this message board. The sound is now loud and strong, but lacks some bass, I'm wondering if I have the same problem as another member on this board that I read about with the cross over wires being wrong... Any quick way to check this? I hope to order the volume 2 service manual soon so I can double check what it is supposed to be. Working good though for now and happy I can play in stereo for the holiday party!

Thanks for the push in the right direction, This board has given me confidence and helped me through working out this bug!

- Jeremy

[ami-man]

Hi Jeremy,

Cold/dry joints are where the solder is cracked around a connection, you will have to look through a magnifying glass (I use the large lit craft type of magnifying lamp) if you can't solder correctly if you find any dry joints then take the amplifier to someone who can.

With regards to which tapping to use for the speaker output the maximum is indeed E7 but you get a reduced output right down to E2.

Black is connected to E1 left (this is the common connection)
Violet is connected to E7 left
Pink is connected to E7 right

If you are in the USA Bruce Wentworth of AB Leisure does repairs/service exchange on these amplifiers.

In Europe I tend to do a lot of repairs to Rowe Ami electronic boards and amplifiers.
I will also ship worldwide.

Regards
Alan

Alan Hood
ami-man
UK