Using a Yellow Jacket 2177N 4 outlet power block to make a DBT:
1. Unscrew four screws on both sides of the yellow jacket to remove the metal bottom cover.
2. Unscrew six screws on the inner box (4 on top, 2 on bottom) to expose the wiring.
3. Cut the two wires (see 3rd picture) and connect them together with a wire nut.
4. Assemble everything back together.
5. Plug in the bulbs, Done!
1. Unscrew four screws on both sides of the yellow jacket to remove the metal bottom cover.
2. Unscrew six screws on the inner box (4 on top, 2 on bottom) to expose the wiring.
3. Cut the two wires (see 3rd picture) and connect them together with a wire nut.
4. Assemble everything back together.
5. Plug in the bulbs, Done!
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I thought the same when they were forbidden, and stashed a lot.
No need to, you can buy all you want by the truckload under their new guise.
Available in different power, of course, I prefer the "real" 53W "75W equivalent" ones as a general purpose ones.
Absolute worst case, you can use a "pencil" quartz halogen lamp, using the proper sockets of course.
Still alive and kicking, only inside a double glass bulb and of course carrying the magic "Eco" or "green" or "high efficiency" labels somewhere on the box. 😱
They work exactly the same: a glowing red tungsten filament inside a bulb.
Most of the stores in the UK are no longer allowed to sell Halogen or Tungston lamps. They are now all LED.
A way around that is the trusty car headlamp bulb and a 12v transformer.
Place the transformer primary winding in series with the mains supply to your Device On Test.
The greater the load; 21W will light easily and 50W headlamp gives more loading before lighting up.
Personally I use a variac and the appropriate test gear if I ever need to monitor current draw.
A way around that is the trusty car headlamp bulb and a 12v transformer.
Place the transformer primary winding in series with the mains supply to your Device On Test.
The greater the load; 21W will light easily and 50W headlamp gives more loading before lighting up.
Personally I use a variac and the appropriate test gear if I ever need to monitor current draw.
240V E27 socket 18W to 42W tungsten halogen.
Sorry, "Eco" halogen 😱
https://www.lampco.co.uk/collections/eco-halogens-candle-bulbs/es
Sorry, "Eco" halogen 😱
https://www.lampco.co.uk/collections/eco-halogens-candle-bulbs/es
My friend wants to use a DBT to power up some vintage radios from storage, but he thinks that he doesn't capable of build a DBT from "discrete components" like those found in the web. So this is my solution!🙂
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In the 1960's and 70's. I came across them in the university electrical labs and from there insisted that all bench work in my subsequent roles used them and large VA isolation transformers. The Testers I made had a momentary pushbutton ON switch so that one hand had to be on the button so that an accidental current through the heart from the DUT could not happen.
As a professional restorer of vintage radios/phonos/tape decks/etc., it's important to note that those old radios require care during initial power-up.
Most of them are "hot chassis" sets that have one side of the powerline connected to chassis.
A 40 to 60 watt bulb in series is a good choice, but let it be known that radios of old age will most definitely require full restorations regardless of initial operation.
And to eliminate any possible liability cases, upgrading with a fuse and polarized power cord is mandatory thing if the item is being sold, to keep the feds from knocking on your door.
Resistors can go out of range, capacitors like the wax types are well-known to fail too.
Old rubber wiring requires replacement, carefully noting its original dressing and orientation under the chassis.
And certain components, like transformers, are not replaceable if damaged by powering them on.
The value of some radios can be lost or greatly reduced if something major needs replacing.
I've done literally hundreds of restorations over the decades for customers, a lot being "family treasures" dating back to the 1920's, and did not have the option of ruining their stuff by carelessness.
Thank you Pano, I appreciate your kind words.
Yes, I think that may help reform the PS caps in those vintage radio since they were in storage for over two decades.
I also suggest to my friend to use shatterproof incandescent bulbs of 25, 40, 60 and 100watts for the DBT, so he can use any combinations to match the load.
Forget about "reforming" those caps on old radios.
Just replace them.
Reforming is nonsense and gambling with fate.
I'm confusing! What is the reason(s) of using a Variac and DBT for?
The variac, besides providing an adjustable AC voltage, also feeds the DC supply transformer, allowing for adjustable DC.
The DBT dual bulbs can be switched in seperately as needed.
Meters monitor things.