BASIC TEST EQUIPMENT. What do I need?
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Hello Guys, tomorrow I have an opportunity to pick up some test equipment from the estate of a deceased radio repairman and collector. Being that I am new to the hobby, I just wanted some input from the experts. I want to be able to do alignments and circuit testing so from what I have gathered through reading I will need a signal generator, signal tracer, variable power supply for the basics. There is an O scope available also. I already have a Hickock TV-7-B/U tube tester and a volt/ohm meter. So what else? I will mainly be restoring 30s thru 50s radios. Thanks for any ideas you can give. Bob
Robert Chesarek
Renfrew, PA
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Hello Bob, by all means, the basic vintage-radio repair bench needs a few basics!! If all test-equip is in good working condition, go for the sig-generator, sig-tracer, and the variac!! All 3 are required for this hobby!! Also, if you see a good ol analog Simpson voltmeter, especially a model 260 in the sale, pick that up as well!! All the above test-equip mentioned will provide you the necessary equip to fully enjoy the vintage radio electronic-restorations hobby indeed!! Just make sure ALL the test equip is in fine working conditions, and you will be set for a fine workbench!!! Also, if you can find a "isolation-transformer", those can keep you safe from accidental workbench hi-voltage accidents on the AC/DC live chassis restorations on radios that dont have a AC transformer on the chassis. Randal
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I find a capacitor tester comes in handy now and then.
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City: Morris Plains, NJ
There won't be much of any use for a power supply; I dont' recall having used one in the last 40 years on radios.
A high impedance AC Voltmeter (hp 400 series) are a requirement for peaking IF's accurately.
A frequency counter is essential if your signal generator doesn't have a read-out.
An oscilloscope is excellent but you must learn to use it properly. That will take time and practice especially in triggers and what to trigger off of.
A high impedance 10:1 divider probe is essential for use with the scope, AC voltmeter, and counter. Using ordinary wire or coax and clip leads into a circuit will load and add capacitance to whatever you are looking at-and you will NOT be getting the results you had hoped for. The hi-Z probe will always look like a 10Meg resistor (nothing!) to a circuit.
Something not always thought about but very important- a cheap external attenuator that will remain forever on the output connector of your sig gen. 10dB is perfect- it will reduce your signal level to one tenth and protect your sig gen from getting fried when you accidentally make connection to the B+ (high voltage). The attenuator will fry instead of your sig gen (been there, done that).
Your signal generator should go down to 175KHz and be capable of 70% AM; better yet a range of audio to 50MHz. IF's are usually 455-470 KHz, but will go down to 175KHz in some Silvertones- that's the only reason for going down to 175KHz.
Pete AI2V
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Bob
Since you already have a tube tester, the other suggestions are excellent ones.
I wanted to add that several Philco sets use low IF frequencies. Models 111, 112, 90, 15, 17 and late version 14 have an IF of 175 kc. Several Philco models, notably Models 70, late 90, 91, 71, 19, 89, 18 and others have an IF of 260 kc.
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Ron Ramirez
Ferdinand IN
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Thanks to everyone for their input and suggestions. I guess I did alright on the equipment I bought. Some of it is old but in good shape and some is newer. Here is what I ended up with:
RCA WR49B Signal Generator tied to a Hewlett Packard 5325A Universal Digital Frequency Counter.
RCA TV ISOTAP WP25A
VIZ Senior Ohmyst WV98C
BK Precision Dynascan 20MHz Oscilloscope M-2120
BK Precision Variable AC Power supply
ECG Capacitance Meter
And an oldie but goodie PACO Z-80 Signal Tracer
Now, if I could only figure out what all this stuff does and where all these wires go I would be in business! Thanks again guys, Bob
Robert Chesarek
Renfrew, PA
signaltracer
Unregistered
I for one really appreciate your post, Bob. I too am a noob at this and have only done recaps and some "armchair" alignments. Been really lucky, but that was also on sets that were already working. This is a good topic with good suggestions, and now I know what I need to be looking for myself.
Sounds like you did well! Repair on!
Charlie in New Hampshuh
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City: Anacortes, WA
I KNEW there was a thread about test gear on the Phorum somewhere!
I've had it pointed out that I've already said, "I could make this a hobby..." enough times that it's already become a hobby, and I have yet to replace my first capacitor.
TODAY'S QUESTION: The Variac. I understand it's a necessary piece of equipment if you want a little more control than a dim-bulb tester. What amperage do you seasoned veterans think would be appropriate? Metered, or will an unmetered unit suffice?
... to quote Mike Myers in Coffee Talk, "discuss."
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From what I've gathered in reading the posts and replies to my questions a 2-3 Amp will be fine. I managed to find a 6A but that was by shear luck. If you don't have a metered one it's real easy to add a meter to the output. Older meters can often be had for next to nothing from friends basements and garages......
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City: Pocasset, MA
A meter will give you an indication of a short before you crank the voltage up too far. Any range up to 5 amps is fine provided the scale is not too crowded below one amp (older AC meters often have nonlinear scales).
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Thanks, folks. I have been considering plopping down $60 on one of those dreaded "cheap Chinese" variacs that I see on eBay (unless I can find a better price, of course), because...
...well, I'll be blunt. Until I get my feet under me in this hobby, I'd rather spend the time working on radios than rebuilding testing gear (excluding tube testers, of course; I know any tube tester I get will have to undergo the same overhaul that a radio would).
Doesn't mean I don't want one of the 40-pound variacs eventually.
NEXT QUESTION: Understanding that a mutual conductance tube tester is pretty much where it's at, what's the diff between mutual conductance and dynamic conductance as far as end results are concerned? I know that Hickok had a patent on "Mutual Conductance," but I'm not necessarily willing to pay $$$ for a Hickok 572 when I can pay $$ for, say, a Jackson 648 and get the same results.
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I'd like a few opinions. There's available, for $25, a Superior Powerstat model 136 20 amp variac. The case is all of 8" in diameter. The wiper squeaks a little when turned, there is no plug on it, no fuse, nor is there a receptical, but there are the appropriate terminals for such. Does this sound like a deal, and if so, which terminals go to the power cord and receptical? Thanks for any advice.
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City: Anacortes, WA
Here's another question--I didn't realize that my time was as quick on this one as it was... does anyone have any experience with "Satan's Choice," the EICO 666 Tube Tester? I'm aware that EICO was a little wonky with their settings, but other than that, any input at all?
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City: Pocasset, MA
The 666 works all right, if it was competently built and cared for. I wouldn't want to ship one very far, with its heavy steel case. It will do 90% of what a Hickok will, for the average user.
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Mikhail7 Wrote:I'd like a few opinions. There's available, for $25, a Superior Powerstat model 136 20 amp variac. The case is all of 8" in diameter. The wiper squeaks a little when turned, there is no plug on it, no fuse, nor is there a receptical, but there are the appropriate terminals for such. Does this sound like a deal, and if so, which terminals go to the power cord and receptical? Thanks for any advice.
Mike
Hard to say on this one. $25 isn't bad, but I would want to know if it was in good shape or if it had been stressed during its "lifetime" (for lack of a better term). Are the input/output terminals not labeled at all?
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Ron Ramirez
Ferdinand IN
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