# Sprague Vitamin Q capacitor?

We recently purchased the estate of a 94-year-old gentleman who was an electronic genius.

He started building radios when he was 14 and was a ham operator and repairman of all types of electronics until the day he died.

We purchased the estate mostly for the ham radio equipment, he built some pretty impressive linear amps and customized his radios in a very high tech manner.

He was also a hoarder and since he also had lots of useful old stock electrical parts we purchased these as well. We are sure there are folks who could use these and we would hate to see them get thrown in the dump by the family.

This gentleman was very well organized and had most everything marked as to what it was, how it tested, and what it was for etc.

The piece I have in question is a large Sprague Vitamin Q Capacitor. I have tried to find anything like it, to compare it to but have found nothing. It is 15" tall and weighs around 20 pounds.

We want to resell this, but do not know what it is for or any of the specs. I have found a few sites that explain the numbering of these, but none that have the information on these particular numbers. We would like to get this in to the hands of either a collector or someone who could use it, so any information on the specs, and what it would be used in would be most appreciated.

Pictures are:

• This is a high voltage paper-in-oil (PIO) glass sealed capacitor. The lower voltage versions of these capacitors are in high demand in the guitar industry for guitar amplifiers due to their supposed ability to deliver desirable tonal quality. They are priced in the $25 and up range. Your particular unit is probably rated at several thousand volts and is not practical for that application. It is possible that the markings mean it has a capacitance of 10 uf and a voltage rating of 4200 volts. – Barry May 27 '14 at 2:22 • Apparently Vitamin Q caps are sought after because the oil that they are made from gives it a warm tone. What is that saying about fool and their money ? I believe that is 10 Farad 4200 Volt cap. – placeholder May 27 '14 at 2:23 • I would say meant for a large radio transmitter or RF gluing machine. – C. Towne Springer May 27 '14 at 2:40 • Caution on the oil filled capacitor. Since you said the old gentleman was a hoarder, the capacitor may have been manufactured before 1979. If so, the oil contained within likely is Polychlorinated biphenyl (PCB). This oil was banned years ago from being used in capacitors and transformers for being a cancer causing agent. – Marla May 27 '14 at 14:04 • It seems that the OP is now currently selling the capacitor on line here for US$ 190. – Joel Reyes Noche Jul 17 '14 at 6:54

From the marking, it looks like 10 microfarad at 4200 volts, non-polarized.

Such a thing would be good for power factor correction on power lines. It might be used in a very specialized power supply, as very few things use voltages that high. Possibly something like a really high powered ( multi KW ) microwave oven circuit could use something like this. Maybe a rail gun or a radar transmitter. Anything requiring a very brief pulse of a lot of energy. Such a thing would be quite valuable to the right person, however any entity needing such a unique device is apt to be an aerospace entity and have the resources to procure one with all the paperwork.

Please be careful with that thing - as you can store a lethal amount of charge in it quite easily should you decide to charge it up on a TV flyback or similar. I would also make sure I had a piece of wire - raw telephone wire would be fine - across the terminals when stored to make very sure that thing does not have any residual charge. That capacitor could easily kill you if you were horsing around with it.

Yes.. it would be worth \$190 to someone who was doing some high energy research.

Incidentally, this is written by yet another 60 year old engineer.

• Would the "DC" on the side not suggest, um, "DC"? I know nothing else about it does, though. – Transistor Jun 20 '16 at 23:01

This post is a bit late, but...the Vitamin Q actually refers to the dielectric oil used. It's a refined paraffin oil. Sprague did use PCB oil, but that came later in their history. The part is hermetic so it's probably still good.

• It's perfectly OK to add salient information, which you did. – placeholder Jun 21 '16 at 3:01

This is a 10 mfd, 4200 volt DC filter capacitor for a high powered radio transmitter. Watch out, it's pre-1979. More than likely this capacitor contains PCB dielectric oil, possession of which will get you a big fat fine from the EPA.

From yet another 60 year old broadcast engineer.

• This is a very irresponsible post. From the EPA website - " Toxic Substances Control Act (TSCA) under TSCA. TSCA bans the manufacture, processing, use and distribution in commerce of PCBs." and they provide guidance on disposal and proper facilities of old equipment. They aren't going to fine you for reporting such a device, they do after all want you to hand them in and get them out of circulation. If you do something stupid, like dump it in a body of water, then yes, they'll go after you. But the last thing they need is scare mongering that prevents people from cleaning up this stuff. – placeholder Sep 22 '14 at 22:28