The Whippany Melosonic or Realistic Musideck combo organ

This little combo organ goes by a few names, depending on who sold it.  That's right, the same organ was made in one place, and branded with a different name for different resellers.  They could be called a Realistic Musideck if sold under the Radio Shack Realistic brand, or a Whippany Melosonic if sold by the Whippany Melo-sonic Corporation.  Inside, the organs are stamped 'Made in Italy', so regardless of what the exterior stamps claim (often they say made in USA on the exterior...) the circuits and keyboard at the very least were made in Italy.  Likely in the Marche Region. These instruments were probably not made in vast quantities, because not many remain today. 

There are a few model variations, one contains a drum machine (the 350), and one doesn't (the 300). All models that we have seen do have a vibrato control, and also all have independent control over the bass volume.  The voice selections for the main voice selections include Flute, Diapason, Horn, Woodwind, Reed, Full Organ.  These selections essentially equalize the same tone to have more highs and cut through more.  

One thing that all of these organs do have in common is their main circuit design.  

To tune these organs there are trim pots which will tune three notes in sections equally. If individual notes within a section are further out of tune, their "tuning" resistor would need to be swapped out.  The individual precision resistors, responsible for each notes pitch, drift over time (like all resistors).  In the case where we are fine-tuning by replacing resistors, we use the following procedure. 

The trim pot will tune the highest pitch note of the three-note set. Set the trim-pot so the highest note is in pitch.  With the instrument turned off we clip out the two precision resistors responsible for the lower two notes of the set - leaving enough lead intact so we can clip onto the leads and test out values. Working from high to low, we replace the resistors with values that lock in their pitch.

To accomplish this effectively you need a wide range of 1/2 watt resistor values. Our resistor stock is very wide and comprehensive, and we still often have to tie resistors together in parallel or series to get just the exact value we need. Being off by +/-  2-5 ohms is usually enough to make a note not quite in tune. 

One more note about tuning - some players expect a degree of "quirkiness" from these keyboards, and that in part can be their pitch not being "perfect". However, I can say from experience we have done some very solid tuning jobs on these, and still felt there was plenty of quirkiness to go around.  

Part of the "quirkiness" is due to the design of the key contacts, and how they have a tendency to give each note a 'rubbery' attack.  Almost like tube sag.  This brings me to another maintenance tip—cleaning the contacts!

One very common issue we find on these instruments is the contacts being totally oxidized.  This will cause a note to either not play at all, squeak in-and-out intermittently, or play at a completely different pitch. The best course of action here is a little isopropyl alcohol, contact cleaner, and if necessary a little scotch pad cleaning.  With a thorough cleaning, they will be back to their rubbery sounding selves.  

All of the portable versions of this keyboard have chrome legs.  These legs are very similar to Wurlitzer electronic piano legs except the bolt is a different size, and the foot is plastic (where as the Wurlitzer electronic piano legs feet are metal).  We have heard of console versions of this organ, which don't have the chrome legs, but instead are on a classic console organ cabinet.