jshorva65
06-25-2009, 06:18 AM
Well, I saw the term "Wobbulator" used in the Alignment Instructions copied by Rider's from original Dumont service literature for a Dumont set while I was restoring it. This particular split-chassis version of the RA-104 wasn't featured in Sams, although there's a Sams for a similar model having its HV cage on the main chassis. I obtained the Rider's manual for that one, and learned that a Wobbulator was the Tel-Instrument Company (TIC) trade name for a specific model of Sweep/Marker apparatus. Looking around a bit, I located two Type 1200A Wobbulator units for sale in upstate NY. ROAD TRIP!!! I ended up scoring both of them along with three "roundie" Zenith color sets, two color CRT's (a NIB/NOS Philco 21FJP22A, and a used 21GVP22A) as a package deal.
One of the two Wobbulator units was in Good condition (minor scratches and dents, but complete), the other in Fair condition (more scratches and dents, missing four of the twelve plastic pushbutton caps). Inside, the units are of modular construction. There are actually eight independent Sweep/Marker Generators inside, one each for the VHF High channels (7-13) and another single unit for the five VHF Low channels (2-6) which shares its chassis with the channel-switching logic, two stepper relays, and an array of calibration controls. There is also a regulated power supply module and a cooling blower inside the 19"x19"x19" metal chassis. The front panel features the On/Off switch, AC Input, Fuse holder, Marker On/Off switches, two fixed and one variable Attenuator, plus RF Out jack, binding posts for scope Horiz output, twelve pushbuttons for the Channel presets, and the Pilot Lamp. I have yet to find a Manual for the unit, but will only need one for Calibration. The circuitry inside was so straightforward and intuitive that I had the recapping done within 2 days of returning from the road trip. When I hooked it up to a scope and demodulator probe, the unit powered up and operated about as well as I expected. The unit produced the expected sounds of: the soft whirr of the blower motor; the hum of the EMR unit(s) (which is louder for the VHF Low channels than for the VHF High due to the approx. 10 MHz sweep width representing a greater deviation percentage at the VHF Low frequencies than at VHF High); and the "thump" of the stepper relays' cycling as I stepped the unit through the presets. The unit powers up, blower runs, switching logic operates correctly, Sweep is produced on all channels, and Markers are produced on most channels. Another swabbing of the stepper relays' contacts with rubbing alcohol and Calibration after I obtain the Manual should allow me to perform tuner alignments with remarkable efficiency for those tuners which needed "major surgery" to restore and to do performance testing of tuners which seem to be working well after simple cleaning. This unit and its sibling unit were once used in the Stromberg-Carlson Co. factory, presumably for alignment of the Mallory Inductuners used in the Dumont-clone sets (like Jamie's TV-12) on the production line. Metal tags attached at the upper left corner of each unit's front panel have "S.C. Co." stamped on them.
Once I get the lighting correct for a video, I plan to post a clip on YouTube of the unit in operation, and title the clip "Whatintheworldisa Wobbulator???" which was inspired by a t-shirt sold in my hometown back in the 70s which read something like "Whereintheworldis Warren, Ohio???"
One of the two Wobbulator units was in Good condition (minor scratches and dents, but complete), the other in Fair condition (more scratches and dents, missing four of the twelve plastic pushbutton caps). Inside, the units are of modular construction. There are actually eight independent Sweep/Marker Generators inside, one each for the VHF High channels (7-13) and another single unit for the five VHF Low channels (2-6) which shares its chassis with the channel-switching logic, two stepper relays, and an array of calibration controls. There is also a regulated power supply module and a cooling blower inside the 19"x19"x19" metal chassis. The front panel features the On/Off switch, AC Input, Fuse holder, Marker On/Off switches, two fixed and one variable Attenuator, plus RF Out jack, binding posts for scope Horiz output, twelve pushbuttons for the Channel presets, and the Pilot Lamp. I have yet to find a Manual for the unit, but will only need one for Calibration. The circuitry inside was so straightforward and intuitive that I had the recapping done within 2 days of returning from the road trip. When I hooked it up to a scope and demodulator probe, the unit powered up and operated about as well as I expected. The unit produced the expected sounds of: the soft whirr of the blower motor; the hum of the EMR unit(s) (which is louder for the VHF Low channels than for the VHF High due to the approx. 10 MHz sweep width representing a greater deviation percentage at the VHF Low frequencies than at VHF High); and the "thump" of the stepper relays' cycling as I stepped the unit through the presets. The unit powers up, blower runs, switching logic operates correctly, Sweep is produced on all channels, and Markers are produced on most channels. Another swabbing of the stepper relays' contacts with rubbing alcohol and Calibration after I obtain the Manual should allow me to perform tuner alignments with remarkable efficiency for those tuners which needed "major surgery" to restore and to do performance testing of tuners which seem to be working well after simple cleaning. This unit and its sibling unit were once used in the Stromberg-Carlson Co. factory, presumably for alignment of the Mallory Inductuners used in the Dumont-clone sets (like Jamie's TV-12) on the production line. Metal tags attached at the upper left corner of each unit's front panel have "S.C. Co." stamped on them.
Once I get the lighting correct for a video, I plan to post a clip on YouTube of the unit in operation, and title the clip "Whatintheworldisa Wobbulator???" which was inspired by a t-shirt sold in my hometown back in the 70s which read something like "Whereintheworldis Warren, Ohio???"