Wurlitzer 206A

details

Steve Graham (now owned by Sam Fribush)

Serial Number: 127281L

Estimated 1980
Model 206A pianos were made from 1974-1983 with the last serial number being 133144L. On back of action rail is stamped 80414047 (code interpreted as YYMMDDXXX). Suggests April 14 1980. Serial number ending in L indicates built at Logan Utah plant.

initial plan for service

Service Log

REGULATE KEYBOARD

Disassemble piano, remove action rail

Inspect & clean capstans

Key easing is not needed

Regulate piano

QUICKEN KEYBOARD ACTION

Remove each whip assembly one at a time and lubricate all 3 action centers (wood/felt/pin) with 8 parts naptha/1 part silicone. Reassemble each whip back into the action rail.

1 broken whip – install new one (lowest note)

Remove hammer assemblies one at a time and lubricate action centers, reassemble.

Lube key posts with Vintage Vibe key post lube

Reinstall keys,

Clean key tops

SET LOST MOTION

Adjust bottom capstan screws (ensuring the jack accurately returns in the hammer butt on slow return of a depressed key)

Install harp

Check that hammers hit center of reeds while avoiding braces

Install damper rails.

Reassemble piano

Top 2 keys (B6 & C6) stick when depressed. The front of hammers’ felt rubbed against the harp assembly – would catch and not release. Filed down front of hammer felts just enough to clear harp assembly.

Check/adjust key height

Adjust damper screws and adjust damper felts so all reeds are equally dampened

Set each key’s let off with regulating capstan screws (evens out loud/soft notes and evens feel)

Voicing – adjust each pickup to bottom of reed to increase or decrease harmonics. On a few softer notes, I adjusted the reed very slightly to one side of the pickup to increase its volume relative to the other notes.

Rebuild Amplifier PCB

Adding Vibrato & Aux Out using Vintage Vibe’s 206A > 200A conversion kit

  • Remove piano’s selector switch pot – install new 50k pot w/ 18k resistor across lugs 2 & 3
  • Remove R57 12k from reed bar preamp

Change components on amplifier board (203724)

  • Remove C22 1mF (used for teacher microphone circuit & adds hiss)
  • Install:
    • R17 4.7k trim pot 1 & adjust to ~ 2:00
    • R13, R14, R15 680k
    • R16 10k
    • R12, R41 27k
    • R18 680ohm
    • R21 & R41 27k
    • R42 120k
    • R43 1.8k
    • R44 15k
    • R46 120 ohm
    • R47 56k
    • R48 180 ohm
    • Q3 & Q4 142083-2
    • Q15 & Q16 (later model versions)
    • C10 22mF 25v
    • C16, C17, C18 .12uF 100v
    • C23 1uF 25v
    • C24, C25 39pF 25v
    • C26 & R59 4.7uF & 25v in series
    • C27 47uF 10v
    • LDR photoresistor
    • Jumper wire & posts

Install amplifier into piano and test – No Sound

Double-check & reflow solder points on amplifier PCB

Install replacement transistors set (27) from Busted Gear:

  • Small signal transistors:
    • TR1, TR2, TR15     2N5089 NPN
    • TR3, TR4                2N5088 NPN
    • TR7, TR8                2N5087 PNP
    • TR9, TR10, TR14      MPSA06 NPN
    • TR12                        MPSA56 PNP
    • TR16                        MPSA14 NPN
  • Output Transistors:
    • TR11                        TIP36C PNP
    • TR13                        TIP35C NPN

Install 1/4″ Aux output and potentiometer under piano left side

Install switch to mute internal speakers (when using Aux Output) under the piano in the old control center cluster.

PARTS

VINTAGE VIBE ORDER #22432

Wurlitzer 206 / 200A 1/4″ Jack Plate $8.00

Wurlitzer 200 Series Lid Hardware Kit $10.00

Piano Key Post Lube $12.50

Wurlitzer 206A Vibrato / Aux Output Kit $90.00

Wurlitzer 140, 200 Whip Assembly – 200 $12.00

Subtotal: $132.50

 

BUSTED GEAR

Qty. 1 Wurlitzer 200A Small-Signal Transistor Kit $ 16.98

Qty. 2 Wurlitzer 200A Output Transistor Kit $ 20.96

Qty. 2 1.5 amp glass fuse with axial leads for Wurlitzer 200A $  9.00

Qty. 4 Pigtail Adapter Springs for 1/4″ fuses $  6.00

Subtotal: $52.94

 

TOTAL PARTS: $185.44

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