Hohner Symphonic 30 organ

[Tubetec]

Is anyone familiar with this unit ?
mid 60's vintage ,previously owned by Noel Reading , theres even a chance Jimi himself graced its keys at some point .

Initially I found the fuse holder/volts selector was bad , I replaced that with an IEC mains socket with 110/240 voltage selector ,
now it powers up ok . Upper few octaves of the keyboard sound ok ,but tuning is suspect . Lowest portion of the keyboard only puts out a hum when the keys are pressed , next section up puts out a glitchy out of tune wonky sound . Vibrato seems to be doing what it should with the various buttons functioning  as they should . Theres a knee opperated lever underneath which should control the vibe intensity ,but instead seems to function like a swell or volume pedal.

There is a manual online at 'Manualslib' and 'Electrotanya' but for some reason I couldnt download it . Schematic is there too , very simple box of tricks , full of megohm value resistors ,that no doubt have drifted well out of spec over the 55 years or so .

link to schematic here :
https://www.manualslib.com/manual/904265/Hohner-Symphonic-30-N.html?page=9#manual

Hopefully someone has renovated this or a similar unit and can advise me where to start or if its a viable job .

 

[Rob Flinn]

You could maybe ask at the Vintage Synth repair & mods group on Facebook.

 

[cyrano]

Downloads fine for me. It's only 1.6 MB, so it could be mailed to you.

 

[PRR]

Downloads fine for me. Did not auto-open but Firefox and Reader often squabble; opened in my Download folder.

What do you want? Just the schematic?

 

[Tubetec]

I'm not getting that telltale 'purple haze' from the regulator tubes so I suspect my frequency divider neons arent opperating ,
its a little awkward to extract the power supply module ,but I'll have another poke around tomorrow and see how we get on . I also suspect maybe theres an issue with the metal rectifier on the 300volt rail  ,maybe the ht winding on the transformer is fried ,
or a leaky electrolytic is another possibility stopping the regulator tubes from arcing up . 

FB  , I dont interact with that monstrosity at all  ;D

Well I can view the 9 page document ok , so in a pinch I can probably screen grab what I need ,
the English language section of the circuit description and the schematic are the bits I need .
The build on this thing reminds me of school days where no music lesson was complete without the old style Hohner Melodica to make sure our So la ti do's were in tune , me and the boys were already listening to ACaDaCa , Quo and Meatloaf  so Ralf Mc Tells 'Streets of London' was wasted on us. 

 

[pucho812]

Here is the downloaded file from the link you provided