Restoring a Supreme Model 560A Vedolyzer
Supreme described the Vedolyzer as a dynamic signal analyzer that "can not only reveal the presence of a signal, and its relative amplitude and frequency, but can also determine the quality of the signal". In another advert they referred to it as a "super voltmeter". It's a combination of a VTVM, a wavemeter, a 3" oscillograph, and a signal tracer and multiple monitoring system. The Vedolyzer was the basic instrument of Supreme's dynamic analysis system called "See The Signal".
This was hi-tech stuff in 1939 for servicing radios and amplifiers under actual operating conditions. And with a name like the "Vedolyzer" how much more Buck Rogers can you get.
The Vedolyzer was advertised for use in combination with Supreme's model 561 RF generator, and I'm still looking for a model 561 to pair with this and my model 562 Audolyzer.
FYI: Check out Mr. Carlson's Lab on YouTube where he has a 4-part series on restoring a Vedolyzer, and as always he does a masterful job. His videos will be a great reference for restoring this one.
This was hi-tech stuff in 1939 for servicing radios and amplifiers under actual operating conditions. And with a name like the "Vedolyzer" how much more Buck Rogers can you get.
The Vedolyzer was advertised for use in combination with Supreme's model 561 RF generator, and I'm still looking for a model 561 to pair with this and my model 562 Audolyzer.
FYI: Check out Mr. Carlson's Lab on YouTube where he has a 4-part series on restoring a Vedolyzer, and as always he does a masterful job. His videos will be a great reference for restoring this one.
This instrument is S/N 101. I'm not sure where Supreme started with serial numbers (companies didn't always, or even usually, start with 1), but regardless this is a fairly early "A" version, probably dating to mid or late 1940. The front panel is in very good condition, no big scratches or dents, and it will clean up nicely. All the knobs are there and the only parts that might need changed are the obsolete Amphenol microphone-style input connectors.
The manual available online for the 560A is from S/N 364, the one in Mr. Carlson's videos looks to be in the 400's, and I've seen a photo online of another in the 500's, so Supreme made hundreds of the "A" model. The "A" schematic is in the September 1945 edition of Radio Service Dealer magazine (RSD), which is available online. The original Vedolyzer model 560 schematic is dated September 1939, with a note that it was revised on 1-13-40, and the instrument was advertised in the Supreme 1940 catalog, which can be found at supremeinstruments.org. The 560A was first advertised in their 1941 catalog, and an ad in the January 1941 RSD offers the 561A Vedolyzer or the 562 Audolyzer in combo with the model 561 generator as a package deal. In the May 1941 RSD Supreme advised customers that the 1941 models would also be their 1942 models, so the 560A was available at least through '42.
The manual available online for the 560A is from S/N 364, the one in Mr. Carlson's videos looks to be in the 400's, and I've seen a photo online of another in the 500's, so Supreme made hundreds of the "A" model. The "A" schematic is in the September 1945 edition of Radio Service Dealer magazine (RSD), which is available online. The original Vedolyzer model 560 schematic is dated September 1939, with a note that it was revised on 1-13-40, and the instrument was advertised in the Supreme 1940 catalog, which can be found at supremeinstruments.org. The 560A was first advertised in their 1941 catalog, and an ad in the January 1941 RSD offers the 561A Vedolyzer or the 562 Audolyzer in combo with the model 561 generator as a package deal. In the May 1941 RSD Supreme advised customers that the 1941 models would also be their 1942 models, so the 560A was available at least through '42.
On the left side is the Vacuum Tube Voltmeter and ohm meter with push button range selection and the zero controls for the meter. The Power switch and Function Selector are right below the zero controls. Near the top left are the Horizontal and Vertical Position controls for the oscillograph, placed on the left for symmetry.
In the center section is the Wavemeter with a range of 65KC to 6.5MC. Below the Wavemeter are the Multiplier push buttons, the input signal selectors, and the three input jacks for the RF, IF and AF probes. |
And on the right side is the 3" oscillograph with Focus and Intensity controls near the top, the Sync Adjustments and Vertical and Horizontal Gain controls below, and Sweep speed selector buttons down the side.
The oak cabinet is sound and only needs some minor gluing before refinishing. This and the Audolyzer, both with their oak cabinets and similar face designs, will make a nice set on my radio bench. My Audolyzer has a gray front panel, not the matching black one, but that's OK, it's still going to look good.
Another nice thing is this unit still has the original metal back panel attached, so I don't have to make one as I did on the Audolyzer. |
Inside, the chassis is covered in dirt and a thick film, probably residue from cigarette smoke. Unfortunately the chromed chassis is very spotted with rust, and battery acid has created a couple of larger rusty spots, one on top of the chassis and one underneath. I'm going to have to disassemble most of the unit just to get everything cleaned and polished.
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Someone has definitely had their fingers in this thing. A lot of capacitors have been changed, and some resistors, but they didn't change all the old paper caps or electrolytics. It appears they were just trying to get the scope section working. And the workmanship was not very good either: long leads, tack soldering and cold solder joints abound.
I see there are also numerous wires and capacitors just hanging loose and one resistor from the video amp even fell out the bottom when I pulled the chassis. Screws and spacers are also missing and I noticed a ground lug hanging in mid-air because its screw was gone. I checked the date codes on the replacement Sprague electrolytics and they're all from 1984, which gives a rough idea of when this mess was made. |
Well, this is a bit disappointing. Someone, who obviously didn't have a clue what they were doing, has pulled the 3AP1 CRT right out of its plug. They apparently were trying to get the tube out of the socket by pulling on the glass body. Looking at the tube's wires, I see they were just soldered at the very tips of the pins and the solder joints gave way before the wires broke, thankfully I guess. The plug's pins were corroded and stuck in the socket and after loosening them up with a little WD-40, I carefully pried out the plug using a small screwdriver. This is why you don't pull on the glass tube when removing a CRT.
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Now I have to try to figure out the pin wiring by peering through the CRT glass to see if I can trace which wires connect to which electrodes. The filaments test good, so it will probably work just fine if I can sort out the rest of the wiring.
With the CRT out of the way the video amp and Wavemeter subchassis have been pulled for cleaning and rebuild. The chrome is not in real good condition but cleaning has restored at least some of its former luster. Next the face plate needs to come off for cleaning and to pull the left and right switch banks.
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This is about as clean as the chrome is going to get, but it's still a lot better than when I started. The video amp will be stripped down and rebuilt with mostly new components since almost all of the old parts are out of tolerance and have to go anyway, and the soldering is pretty bad, well, except for the parts I see that aren't soldered at all.
Interestingly, the video amp specs of the original model 560 claimed to have a flat bandwidth of 4.5MHz, but the updated 560A only claimed 2.5MHz. Sounds like the original design had some issues and didn't live up to expectations.
Interestingly, the video amp specs of the original model 560 claimed to have a flat bandwidth of 4.5MHz, but the updated 560A only claimed 2.5MHz. Sounds like the original design had some issues and didn't live up to expectations.
There are several components in the Wavemeter to check and replace. I removed the Wavemeter coils and stashed them in a cabinet until I'm finished under the chassis. Too many delicate wires there to take a chance.
Not much left on top of the main chassis now that the front panel is off. I will start rebuilding this section first and then move on to the other modules afterwards.
I already see the Horizontal Position control is not original and needs replaced. It's very hard to turn, cleaning would probably fix that, but it's not even the correct value. The other pots look original and all will get cleaned.
I already see the Horizontal Position control is not original and needs replaced. It's very hard to turn, cleaning would probably fix that, but it's not even the correct value. The other pots look original and all will get cleaned.
Now that I'm actually replacing components under the chassis I am really discovering just how hacked up it is. I was wondering why all the lacing had been cut away from the wiring and now I know after some late nights tracing down wiring and component mistakes I'm finding. Plus I have to clean and resolder every solder joint that whoever did this has touched. Many terminals are just covered in globs of solder.
I also see there is a switch on the Horizontal Gain control that is not shown on the 560A schematic. But I did finally find it on the old model 560 schematic. Apparently it was carried over from the 560 design and looks to be another example of Supreme's incremental design changes over time, as the switch really has no purpose in the 560A. The switch connected the CRT"s horizontal plate to either the output of the internal horizontal amp or an external input jack labeled Horiz. Plate. But there is no Horiz. Plate jack on the 560A so I just grounded the wire that was supposed to go to it. |
In all I found two bad potentiometers. One is the aforementioned Horizontal Position control and the other is the Meter Zero pot. On it the wiper connection is a coiled "spring" around the center shaft and solders to the center terminal. The spring wire had broken at the terminal, but I was able to solder it back and save the pot.
The left and right push button racks have been cleaned and are operating smoothly, but I notice on both sets that there were originally rubber pieces around each shaft at the inside tops of the plungers, to keep them from hitting the frame with a loud 'clack" when they pop up. I'll see what I can do about fabricating replacements.
The left and right push button racks have been cleaned and are operating smoothly, but I notice on both sets that there were originally rubber pieces around each shaft at the inside tops of the plungers, to keep them from hitting the frame with a loud 'clack" when they pop up. I'll see what I can do about fabricating replacements.
The front panel has been cleaned and polished, and the two push button switch banks pulled, restored, and reinstalled, so now I want to get the front back on quickly to lessen the chance of breaking any wires on the components that are just hanging loose without it. I added flat washers under all the potentiometer nuts to protect the front panel finish, with the exception of the Focus and Intensity pots, which are insulated from the front panel by phenolic washer sets. I also removed the internal-tooth lock washers from under the heads of the fillester head screws that attach the front panel to the chassis. The toothed washers were digging into the aluminum panel and ruining the finish around the screw holes. But there are still external-tooth washers under the nuts on the chassis side.
While waiting on parts I created a graticule using a scan of one from the Supreme site. The lines on this one are not printed but cut into a heavy piece of plastic with an exacto knife and then filled with a black paint pen. The lettering is also done with the paint pen. It slips under the three little ears on the front of the bezel. This particular graticule would be for use with the model 561 generator in sweep mode.
After several late nights at the bench the video amp is finally ready to reinstall. Almost every resistor and capacitor has been replaced. Some resistors were wildly out of spec, double or triple their marked values. A lot of the capacitors had already been changed once, and the orange dip caps are good film caps, but I don't like their radial style leads for point-to-point wiring like in the video amp, so I replaced all but a couple with axial lead film capacitors. All the old hard-as-a-rock rubber grommets were replaced and new B+ and -Bias buses were made from 14awg solid copper wire.
Some resistors did not match either the value or wattage shown on the schematic. Thanks to the poor workmanship by the mystery mangler, it was fairly easy to tell which components were from the factory just by inspecting the lead wraps and soldering. All the component differences I found appear to be factory. I even checked Mr. Carlson's videos to compare with his Vedolyzer and he had the same changes I found in mine. So I'm editing the schematic as I go. I've also found some components that are not on the 560A schematic but are on the 560 schematic. More examples of incremental changes I guess.
Some resistors did not match either the value or wattage shown on the schematic. Thanks to the poor workmanship by the mystery mangler, it was fairly easy to tell which components were from the factory just by inspecting the lead wraps and soldering. All the component differences I found appear to be factory. I even checked Mr. Carlson's videos to compare with his Vedolyzer and he had the same changes I found in mine. So I'm editing the schematic as I go. I've also found some components that are not on the 560A schematic but are on the 560 schematic. More examples of incremental changes I guess.
Under the Wavemeter subchassis I replaced all three resistors and two of the three capacitors (the mica was OK) that connect to the Multiplier switches. I ran into a small problem replacing the resistors, the leads on my modern film resistors are just a little too short. I had one older 1/2-watt film resistor with longer leads for the 4K ohm resistor, but had to dig through my 1-watt carbon comp resistor drawers to come up with the other two replacements.
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The underside of the chassis is ready for testing. This has been a whole lot of work getting it back to this point. The three input connectors have been changed to UHF connectors because they are a perfect fit for the holes, and adapters to BNC are easy to get. The original single pin microphone connectors are obsolete and unavailable unless you can find used ones. I'll bag the originals and keep them for the unit in case I'd ever want to put it back to factory.
All the pin jacks were also replaced with a matching-style banana jack, because all my patch cables use banana plugs. But again, I'll save the originals.
I added a 2-cell AA battery holder for the bias batteries. This way I don't have to solder directly to them. The original battery clamp was also AA size, or whatever the equivalent was back then.
The two original power supply filter caps were in a box mounted to the rear of the chassis and had already been removed. So I made a minor wiring change to the terminal boards where the filter wiring originally tied in, so I could mount the two replacement electrolytics right to the terminal boards.
All the pin jacks were also replaced with a matching-style banana jack, because all my patch cables use banana plugs. But again, I'll save the originals.
I added a 2-cell AA battery holder for the bias batteries. This way I don't have to solder directly to them. The original battery clamp was also AA size, or whatever the equivalent was back then.
The two original power supply filter caps were in a box mounted to the rear of the chassis and had already been removed. So I made a minor wiring change to the terminal boards where the filter wiring originally tied in, so I could mount the two replacement electrolytics right to the terminal boards.
On the top side I have tested and reinstalled the tubes, and replaced a gassy 1852 tube plus swapped the 6AG7 (it tests good) for one that tests better. The 6AG7 tube socket pins were very loose, causing intermittent operation, and were tightened up. I reinstalled the CRT's plug and tested it to see if I have the pins sorted correctly. It works but the brightness is low and the focus seems off (possibly A1 and A2 are swapped), so I replaced it with a new JAN 3AP1 CRT which works fine. I'll figure out the old CRT later. I also added another battery holder on top of the chassis for the ohmmeter batteries. It holds two "D" cells and is attached to the original battery plate with thumb screws so it can be removed for easily installing new batteries.
The round can capacitor mounted on top near the CRT is the 0.5uF 1500VDC filter capacitor for the CRT high voltage. It tests good so I left it installed. I looked it up in an old capacitor catalog and it is oil-filled with an oil that contains PCBs. So it should never be opened and should be carefully disposed of if it ever shows signs of leaking. One of the hazards of restoring vintage equipment.
The cabinet has also been repaired and refinished and is ready for the chassis as soon as testing and alignment are finished.
The round can capacitor mounted on top near the CRT is the 0.5uF 1500VDC filter capacitor for the CRT high voltage. It tests good so I left it installed. I looked it up in an old capacitor catalog and it is oil-filled with an oil that contains PCBs. So it should never be opened and should be carefully disposed of if it ever shows signs of leaking. One of the hazards of restoring vintage equipment.
The cabinet has also been repaired and refinished and is ready for the chassis as soon as testing and alignment are finished.
To summarize all the new parts installed to this point, I've replaced 46 resistors, 41 capacitors, 1 potentiometer, 2 1852 tubes, the dial lamp, 22 grommets, 3 input connectors, 6 pin jacks, the power cord, a broken fuse clip, most all of the hardware on the chassis, all the 3/8" front panel nuts, and added 3/8" flat washers to protect the panel's finish. I've also installed 2 battery holders and made 9 brass standoff spacers to replace missing ones for the terminal boards, and purchased fillester head screws to replace some missing ones on the front panel, 2 new handles to replace the missing ones on the cabinet, 4 new rubber feet, and all new hardware for mounting the unit in the cabinet and attaching the rear panel. And I replaced the 3AP1 CRT. I think that about covers it.
Testing revealed a few minor issues such as loose pins on several tube sockets, two jumpers I forgot to reinstall when replacing some resistors, and I found some more components that are only on the original 560 schematic. Another 1852 tube was either very microphonic or had an intermittent internal short and was replaced. It caused the scope trace to jump wildly just by tapping on it. Also, when focusing the CRT, the Focus control was near maximum clockwise rotation. To bring the focus point back towards the center of the control I made a small modification by changing the 100K resistor between the Focus and Intensity controls to 200K.
The B+ high voltage is about 300 - 310V depending on the function selected, and the CRT high voltage is about -1000V. While on the subject of high voltages, a WARNING about the Vedolyzer chassis is in order. This is a dangerous chassis to work on because the component mounting strips running along the inside walls on both sides of the chassis expose hazardous voltages right along the edges of the chassis, right where you could easily brush against a high voltage terminal while testing or, if this unit is powered on out of its case, for example, and someone tries to move it by slipping their fingers under the edges to pick it up, there is a very good chance of putting your fingers directly on one of these high voltage points. There is also a chance of putting a finger directly on the AC line voltage.
And there are also other exposed points with high voltage present, such as on the terminals of some of the front panel's control potentiometers. CAUTION needs to be exercised and you're proceeding at your own risk.
The B+ high voltage is about 300 - 310V depending on the function selected, and the CRT high voltage is about -1000V. While on the subject of high voltages, a WARNING about the Vedolyzer chassis is in order. This is a dangerous chassis to work on because the component mounting strips running along the inside walls on both sides of the chassis expose hazardous voltages right along the edges of the chassis, right where you could easily brush against a high voltage terminal while testing or, if this unit is powered on out of its case, for example, and someone tries to move it by slipping their fingers under the edges to pick it up, there is a very good chance of putting your fingers directly on one of these high voltage points. There is also a chance of putting a finger directly on the AC line voltage.
And there are also other exposed points with high voltage present, such as on the terminals of some of the front panel's control potentiometers. CAUTION needs to be exercised and you're proceeding at your own risk.
There aren't any alignment instructions available that I could find, but the schematic gives a few clues. First, there is no separate calibration for the ohm meter. It's calibrated everytime you zero it and adjust inifinity. Next, the three VTVM calibrations are not labeled on the 560A schematic, but they are on the old 560 diagram, and are the DC Cal, AC Cal, and Common AC/DC Zero adjustments. These are the three trimmers on the terminal strips under the chassis. Before starting the calibration I set the mechanical zero of the needle. Then I set the Common AC/DC Zero trimmer to around mid range as a starting point. Not sure if I really needed to but I did. Then to calibrate the voltmeter I selected DCV and zeroed the meter with the front panel control. I selected the proper range, applied the calibration voltage, and set the DC CAL trimmer for the correct reading on the dial. Next I removed the voltage and readjusted the front panel zero and repeated the steps to refine the calibration. With that done I moved on to the AC calibration.
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To calibrate the AC scales set the selector to ACV, but DO NOT zero the meter using the front panel control. Leave the front panel zero exactly where it was after the DC calibration. Instead use the AC CAL trimmer to zero the meter. Then apply the calibration voltage and tweak the very same AC CAL trimmer to set the correct voltage reading. It should only take a very small readjustment. Then remove the voltage and recheck meter zero, resetting it back to zero using the COMMON AC/DC ZERO trimmer, if needed. Reapply the calibration voltage and if the reading is off retweak the AC CAL trimmer again. Recheck the zero and retweak the COMMON AC/DC ZERO if needed. You can repeat these two steps to refine the calibration. Now when you switch between DCV and ACV the needle should remain on zero. That's it for the VTVM.
If the VTVM isn't calibrating then check the resistors associated with the 6J5. I had to replace all the fixed resistors because they had drifted high.
I did not replace any of the hand picked range resistor pairs for the VTVM or ohm meter. The accuracy on different ranges was still close enough to just leave them.
If the VTVM isn't calibrating then check the resistors associated with the 6J5. I had to replace all the fixed resistors because they had drifted high.
I did not replace any of the hand picked range resistor pairs for the VTVM or ohm meter. The accuracy on different ranges was still close enough to just leave them.
The Multiplier adjustments had all been turned full counterclockwise by that certain someone. They are the three trimmers accessible through the holes in the rear of the Wavemeter sub chassis (one hole is behind the first 1852 tube), plus there is the trim pot soldered to the back of the dual Vertical Gain pots.
Looking at the schematic again, these pots all have the same range of adjustment, but in multiples of 10. The total Multiplier resistance for the x1000 range is 40-60Ω, x100 is 400-600Ω, x10 is 4K-6KΩ, and on x1 there isn't a resistor or potentioneter on the switch, instead the resistor/potentiometer combo is connected at the common output of the switches and is 40K-60KΩ (it is in common with all Multiplier positions and is the basic gain adjustment). Since the center of these ranges (presumably the design point) is a multiple of 50 I preset all the controls to give a total resistance of 50Ω, 500Ω, 5KΩ, and 50KΩ. That should be close enough until I can figure out how to fine tune them. These adjustments were made with the Vedolyzer power turned off. |
The Wavemeter bands are adjusted just like aligning a radio. Starting with Band A, I adjusted the coil on the low end and the trimmer capacitor on the high end, and repeated until both were spot on. Then I moved on to the next band.
There are also a couple of trimmers in the video amp which I left at their factory settings. When in doubt, and it still has the factory seal on it, I just leave it alone.
There are also a couple of trimmers in the video amp which I left at their factory settings. When in doubt, and it still has the factory seal on it, I just leave it alone.
It's finally back in its cabinet and all functions are working. I think the Vedolyzer will prove to be a really useful piece of test gear and it and the Audolyzer are going to be two of my favorite instruments on my radio bench.
Page created 6/3/2020
Last edited 8/20/2020
Last edited 8/20/2020