Whatintheworldisa Wobbulator???!!!

[bandersen]

Watch one in action on youtube in one of my favorite channels - radioam232.

[jshorva65]

Essentially, the TIC Type 1200A Wobbulator (left photo) will create the same type of Sweep/Marker display when connected to an oscilloscope and to a TV tuner under test as does the Eico model 368 Sweep/Marker Generator (right photo). Since both units are capable of producing a Sweep/Marker display, it might seem redundant to have both units available. The continuous coverage offered by the Eico unit of frequencies from a few MHz to a few hundred MHz allows exceptional versatility by allowing the unit to be used in multiple similar applications (FM and TV IF in addition to the tuner response curves which either it or the Wobbulator can plot). The advantage of the Wobbulator for tuner alignment lies in its pushbutton presets for each TV channel. Center frequency, marker frequencies, sweep width, and phasing are set for each channel at the press of a button, eliminating the need to adjust these parameters manually for each channel to be aligned as would be necessary when using the Eico 368.

Complete alignment of a vintage TV set such as an RCA 630TS or a Dumont RA-103 can be done far more efficiently with both units on hand. The Eico 368 would be used for the Sound and Picture IF portions of alignment by manually tuning it to two sets of parameters (one each for the Sound IF and Picture IF alignment procedures), then using the Wobbulator and its twelve presets to display the response curves of each channel while aligning the tuner.

I am also awaiting the arrival of another recent score in the category of efficiency-enhancing tools for TV alignment. I expect the RCA WG-295B Video Multi-Marker unit to arrive tomorrow, NIB with its Manual. I'll know more about the unit after I have it in hand, but my preliminary assessment of it from photos I have seen indicates that it is a passive device which "splits" a single reference marker frequency to produce additional markers at fixed intervals from the source frequency. The unit itself is quite small, probably too small to contain any active circuitry (tubes and the power supply required for operating them), which is why my preliminary impression of the device is that it must use passive circuitry. It produces the series of markers shown in the Alignment sections of 1940s/1950s-era RCA service literature. I've been looking for one of these units for some time. It was pictured in a photo of a sample TV alignment workstation from a TV/Radio Servicing textbook I had read nearly 30 years ago. The text identified the unit as a "Video Multi-Marker" without listing model numbers for any of the equipment in the photo. After some research, I was able to identify all of the instruments shown in that photo.

[Dan Starnes]

Very interesting to know what one actually is.

[jshorva65]

Originally Posted by jshorva65

I am also awaiting the arrival of another recent score in the category of efficiency-enhancing tools for TV alignment. I expect the RCA WG-295B Video Multi-Marker unit to arrive tomorrow, NIB...

The RCA WG-295B arrived with the box, but the seller is still looking for its manual since all the accompanying literature was kept separately in file folders by the original owner. As I had thought, it is a passive device. Inside the unit is an cascaded array of LC resonant circuits. A cable with an Amphenol microphone plug exits one end of the case, an Amphenol microphone jack is mounted on the other end of the box. On the front panel is a Markers In/Out switch and a row of rivets inserted into a phenolic insulator. In use, the unit was designed to be connected between a Marker Generator such as the WR-99 and WR-70 Marker Adder, which then connected to a Sweep Generator such as WR-69. Those four units together produced Sweep with Post-Marker Injection universally for 24 MHz and 44 MHz IF and for RF alignment. Setup, however, needed to be done manually for each channel.

Although the Type 1200A Wobbulator provided pushbutton presets for sweep and marker parameters, simplifying setup, it did not offer the superior performance of post-marker injection.