GEM Caravan repair help

[ctyler]

Hi

i just got a Caravan (see attached picture) which I believe was made by GEM. There isn't much online about it. Anyway, it mostly works. The problem is that the B, A#, A, G#, F#, and F keys only play correctly on the top octave. The lower octaves (for those specific notes only) play the highest octave notes instead. While it sounds quite comical when trying to play, I would of course like to fix it.

If anyone has experience of fixing this kind of issue i'd really appreciate some assistance. I checked all soldering and all contacts seem ok. No black marks on capacitors, I read somewhere that the octave divider might be at fault, but I have literally no idea what i'm doing or what's what; I don't even know what it looks like!



If you need further pictures please specify and i'll upload.

thanks, and really hoping you can help me out.

[ctyler]

i got an answer at organforum, it was 2 of the 4 ICs that need replacing. Thread and more pictures are at www.organforum.com/forums/showthread.php?14940-Caravan-%28GEM-%29-compact-organ-help-please&p=217063&posted=1#post217063 so if you think you can help (finding replacement ICs) please contact me on either forum. Thank you

[ctyler]

Ok, don't all rush at once! Problem was solved by replacing 2 of the 4 IC's. The guys at The Organ Forum helped identify the problem and I got the replacement parts from the excellent Vintage Chip in Italy.






Can you hear the echo in here?

[joelindsey]

The custom red top looks awesome! I might have to do the same to mine. I also have the same issue with my B and Bb keys. It's intermittent, however, and seems to go away if I press the key hard or tap it a bunch. Yours must be a newer model, because my Caravan has much larger cards and has transistors instead of IC's. I'm trying to fix the vibrato as well. No idea where to go with that. Glad to see everything worked out!

[ctyler]

i haven't checked back here for a while, sorry for the late reply. i don't know how to help with the vibrato problem.

the red top is a roll of sticky backed plastic from the DIY shop (hardware store to those in the US): also available from art supppliers. It cost 5 euros for 1x3m roll.

If you try it, be really careful as it's extremely tricky getting it on without bubbles or creases. The other thing to note is that it isn't too hard wearing, so if you gig it you'll need to replace it occasionally. But it does look pretty cool.

As for the sound, through a tube amp with the gain high it's amazing sounding.