View Full Version : Whatintheworldisa Wobbulator???!!!


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???"

Sandy G
06-25-2009, 06:26 AM
Warren, Ohio, was also the original home of Packard, one of the finest motorcars that was ever made...

merrylander
06-25-2009, 06:38 AM
Ask the man who owns one.

Sandy G
06-25-2009, 06:57 AM
Ask the man who owns one.

Yep...Too bad you can't really do that much anymore. The Packard club people, however, are fiercely proud of their cars. But the last "real" new Packard you could buy was a '56...The 1957-58 "Packardbakers" are best forgotten. Getting back on topic-What a strange concept for a ardent thread hijacker like me- "Wobbulator" seems to be more of a British term than one used on this side of the pond. I've seen it used in some of the seditionist Boatanchor propaganda I have perused, typically in conjunction w/the Racal RA-17, which was the Brit answer to my beloved Collins R-390A...

electronjohn
06-25-2009, 08:34 AM
It's just a Wheelabrator that wobbles, that's all.

merrylander
06-25-2009, 09:26 AM
It is a European name for a sort of sweep generator.

mhardy6647
06-25-2009, 12:39 PM
next someone'll be asking about snivets...

Arkay
06-25-2009, 01:01 PM
I thought a Wobbulator was something Charlie used in the Chocolate Factory... or was it one of those pieces of gear behind the Wizard of Oz's curtain?
:D

Warren, Ohio, was also the original home of Packard, one of the finest motorcars that was ever made...

OOOooooh, yes, truly outstanding automobiles. My "dream car" is a long-wheel base Packard V12, circa 1937. Supremely elegant design, very luxurious, whisper quiet, and able to handily overtake freeway traffic all day long with a monstrously powerful engine (if you dare to push any car that old, that hard). Enough weight/mass to crush the daylights out of almost anything else in a collision, too... although the thought of crashing one of those beauties makes me cringe! :nono:

Ask the man who owns one.

I wish... one day!


next someone'll be asking about snivets...

Cowardly wild cats, right? [A contraction of "snivelling civets", of course.]
Or are they snipped-off rivets?
:D

Phil Nelson
06-25-2009, 01:11 PM
I have an unrestored Triumph Oscillograph-Wobbulator, built for the Navy under a wartime contract.

http://www.antiqueradio.org/trium01.htm

Cute little bugger. I've had it more than 10 years -- guess I should either restore it or send it packing. Somewhere in my paper piles is the service manual.

Phil Nelson

Whirled One
06-25-2009, 08:00 PM
Weeblators wobbulators but they don't fall down.

7"estatdef
06-25-2009, 08:08 PM
The first time I ran into the term was in a 1939 GE H-87 radio manual. It was used to adjust the IF stages to give a even/broad curve for hifi responce. Akin to a sweep generator.
Terry

zenith2134
06-25-2009, 08:59 PM
News to me! Cool...

cbenham
06-25-2009, 11:56 PM
[QUOTE=7"estatdef;2837099]The first time I ran into the term was in a 1939 GE H-87 radio manual.

In the 1950s one TV manufacturer included a 'wobbulator' circuit in a few sets to make the scanning lines disappear. It was a ~14 megacycle power oscillator driving a third yoke coil that moved the beam vertically by a very small amount, but just enough that it covered the blank areas between the lines on the screen without making the picture look out of focus.
I don't remember which company did this but maybe someone reading this does???
Cliff

David Roper
06-26-2009, 12:35 AM
Yes Cliff, I remember reading about that application too, but only in connection with British TV set manufacturer(s?). I could see a greater desire for it there since the lines themselves are a good deal more pronounced on the 405 line sets once you get up to 21" screens.

ChrisW6ATV
06-26-2009, 12:40 AM
Wobulation (with only one B) is also a recent term used with DLP TV sets. It refers to making a lower-resolution DMD panel create a higher resolution by reflecting light in multiple angles, more or less.

bandersen
06-26-2009, 02:53 AM
Watch one in action on youtube in one of my favorite channels - radioam232 (http://www.youtube.com/watch?v=oaCL3yipJ5M).

jshorva65
06-26-2009, 04:23 AM
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
06-26-2009, 03:22 PM
Very interesting to know what one actually is.

jshorva65
06-28-2009, 04:36 AM
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.