Hi Folks! Today for your consideration, I’m offering a working, recapped Sprague TO-4 Capacitor-Resistor Analyzer that looks almost new inside! The unit even has the original tag on the outside, and a very good looking (but brittle!) leather carrying handle. The serial number stamping is smeared, as best as I can tell, the number is 344642. Unit comes with a reprint of the manual. All in all, this is one of the top three TO-4’s that I have ever seen (and I’ve restored plenty!). It’s only been beaten out by two others that were simply amazing (and this one is no slouch!). The tester reliably and reasonably accurately measures the capacitances of all types of capacitors from around 10 pF-2000 uF and resistances from 2.5 Ohms to 25 Meg Ohms. It will also check wiring and other high resistances, AND reform electrolytic capacitors! If you are working with older electronics or tube equipment, this is THE piece of test equipment to get! The display uses a type 1629 Magic Eye tube as an indicator. The tube that came with the tester was OK, but not strong, so I took the liberty of replacing it with a much better tube. I checked the other two tubes on my TV-7 military transconductance tester for quality and shorts. Both the12J5 and the 1619 are healthy, and way above minimum test values. The 12J5 reads 116 with 50 being minimum. The 1619 reads 87 with 43 being minimum. I have replaced all of the leaky “Black Beauty” (also known as BBoD or Black Beauty of Death caps for their horrendous leakage) capacitors. NONE of paper foils I have checked in any of the many TO-4’s I’ve worked on were good. Some of the bypass caps in this unit were leaking down to 1.5 MegOhms. The two paralleled 1uF caps were essentially dead shorted with only 50 volts on them! Many of the caps were so leaky that they would not test on my Sencore LC-75. The wiring harness looks very good, with minimal cracking. This series is known for brittle wiring. Due to severe cracking which exposed bare wires, I had to replace the original two prong line cord with a three prong, grounded to the chassis line cord. I also installed an inrush current protector: This gives the tubes a “soft start”, and keeps the filaments alive longer due to less startup stress on them. IF SOMEONE OFFERS YOU A TO- SERIES ANALYZER AND THE PAPER FOIL BYPASS AND REFERENCE CAPS HAVEN’T BEEN REPLACED, RUN AWAY! THINGS WILL ONLY END IN TEARS FOR YOU, AS THE CAPS ARE ALL LEAKY, THE INSTRUMENT WON’T BE ACCURATE, AND THE UNIT WILL ULTIMATELY FAIL. More importantly, I made sure the replaced reference capacitors used to set the base line for readings were dead nuts on value. If they aren’t right, the test set won’t be as accurate as it can be. That’s why the values I got testing my set of reference caps were so close to their actual values! Here’s the test results: CAP READING 10 pF 8 pF (C1 scale) 10 pF 10.3 pF (C5) 100 pF 107 pF (C1), 100 pF 112 pF (C 5) 200 pF 199 pF .001 uF .000950 uF (C1), .001 uF .00108 uF (C2) .005 uF .0052 (C1) .005 uF .0054 uF (C2) .02 uF .0199 uF .1 uF .98 uF (C2) .1 uF 1.1 uF(C3) .5 uF .52 uF (C2) .5 uF .525 uF (C3) 2 uF 2 uF 33 uF 34 uF 50 uF 52.5 uF (C3) 50 uF 55 uF (C4) 103 uF 112 uF And with resistors: RES READING 47 Ohms 45 Ohms 5.6 K Ohms 5.4 K Ohms 470 K Ohms 460 K Ohms I did check the insulation resistance scale, and it was off. A 1000 MegOhm high voltage probe read around 1300 MegOhms. This is pretty typical for all TO4’s. Use this scale for relative “go/no go” leakage readings. As mentioned earlier, the unit will reform electrolytic capacitors. I checked, and it will provide up to 650 volts DC, more than enough to reform whatever you have for (of course, use a voltmeter to make sure you don’t exceed capacitor ratings!). The caps in the pictures under test are either a .02 uF or .5 uF, and the resistor in one of the other pictures is a 470K Ohm resistor. Cosmetics are reasonable for the age of the instrument: The front panel does have some very minor paint scrapes and scuff marks. The pictures don’t show it, but the front panel has tiny black paint speckles in some areas, they look like original paint overspray. One original screw was missing, so I replaced it with a similar type. I did carefully clean the front of the instrument and the knobs. I only selectively cleaned the case to preserve the fragile label on the back. The meter movement works as it should. The meter face is slightly off color and has minor haze, I’m not sure if it’s glass or plastic (I’ve only seen glass up to now). This series usually suffers from meter scale mottling, but this movement is in pristine condition. I’m selling this unit because I have a TO-6 as a Daily Driver, so the TO-4 is surplus to my needs (I have way too much stuff!). Also, I thought I had sold my last TO4 earlier, but most unexpectedly found this one on the shelf. THIS IS THE LAST ONE THAT I HAVE. If you want a T04 that’s been restored by me, this will probably be your last chance for quite a while, as I have not purchased any in the last couple of years. Reserve on the analyzer is $125. With the superior condition this one is in, if I can’t get that for a working, overhauled, tested and guaranteed unit, it’s simply not worth parting with. Check out the other units being offered, and you’ll see that this is easily the best documented, functional unit. To sum things up, the analyzer is fully functional within its quirks, and I will give you a three day inspection guarantee on it! You can see that this is definitely not the typical Ebay pig in a poke, and that the item has value and promise. It leaves here working well! Check my feedback, and bid with confidence! *********************************************************************************************************** PLEASE NOTE: If you see a higher than expected shipping price, go to the right of where you see the shipping price. Click on “see details”, which lists all of the options! For some reason, the more expensive options tend to be listed first. *********************************************************************************************************** Packed weight will be approximately 20 pounds. UPS, USPS and Fed Ex are all good shipping options. I am adding a $10.00 charge to cover the cost of the packing materials, as I have had to buy them, and I want to make SURE the unit isn't damaged in transit! Any test equipment, body parts, props, pets, parts, children, gold bars, “B” Batteries, etc. in the background are strictly incidental and not part of the auction! We take PayPal, and are happy to take cash for local pickups. I am usually able to ship within 24 hours of payment. On rare occasions, it may take me a little longer to get the item out due to work and other responsibilities. Please feel free to ask questions, I’ll answer them as best as I can. Check my feedback, and bid with confidence! 30+ years professional electronic technician/engineer, Master Certified Electronic Technician, FCC GROL licensed, 35+ years Amateur licensee, now Amateur Extra. Thanks for viewing this auction! -Tom Herman, PhD., CETma N1BEC/7
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