Share your useful testing apps, I'll start

[Eldorado828]

I know we all do some testing on our benches and not everybody has all the professional testing equipment. Either we're not on our well equipped bench or you need something on the fly so we at times have to improvise. With so much at our fingertips in this very technological age that wasn't at our disposal 15 to 20 years ago, I'm curious to see what some of you fellas have as quick smartphone or tablet tools. Share yours if you will. I'll start with one I've used a few times to put a test tone into a mic.

 

[Jay Mojave]

Yeah a great subject. A quick and easy way to verify the audio amplifier circuit in a radio is to touch the center pin on the volume control, if you hear a hum or noise this verifies the audio circuit is working. Try not to touch any thing else in a tube radio as high voltages are in there. I use a screw driver that has black tape insulate the shaft exposing the tip.

Jay in the Grate Mojave Desert

 

[nomadradio]

Where I come from we call that the analog manual digital signal injector.

Poking it into the input of a radio's 455 kHz IF usually produces raucous noises. Used to have a AM radio station with a gospel format's transmitter a couple of miles away. Sure surprised a customer or two when I poked the output of the AM ceramic filter and a revival preacher came roaring out of the speaker.

Halleluia! The IF stage is working.

73

 

[CbRadiosPRONTO]

I have used the tone generator in a pinch. Normally I’ll use my Rigol on the bench.

The other thing I’ve used is CommTekk’s SINAD. Unfortunately, it’s not a “smartphone” or “tablet” tool or ap. But, it does a good job as a receiver alignment tool. On my main bench, I’ll use my old SINADDER 3 and HP RF generator. Both can cost some dough and the Hp is Yuge. The software is cheap and takes a computer you probably already have.

 

[Monk]

I know we all do some testing on our benches and not everybody has all the professional testing equipment. Either we're not on our well equipped bench or you need something on the fly so we at times have to improvise. With so much at our fingertips in this very technological age that wasn't at our disposal 15 to 20 years ago, I'm curious to see what some of you fellas have as quick smartphone or tablet tools. Share yours if you will. I'll start with one I've used a few times to put a test tone into a mic. View attachment 34500

This isn't an "APP" but more of an old fashion piece of test equipment.
I took an old 23 channel radio and brought out a transistor socket to the outer cover from the final spot on the board to test finals without soldering in. Cheap! Pulled the radio final first of course.
Reason: Cheap fake ebay finals.

Monk

 

[guitar_199]

This isn't an "APP" but more of an old fashion piece of test equipment.
I took an old 23 channel radio and brought out a transistor socket to the outer cover from the final spot on the board to test finals without soldering in. Cheap! Pulled the radio final first of course.
Reason: Cheap fake ebay finals.

Monk

Just curious.... can you test different part numbers? I mean... does that method work well enough to show whether the "test transistor" works.... even though the original 23 channel radio MAY NOT have used that part? ( I hope I am making sense...)

 

[Monk]

Just curious.... can you test different part numbers? I mean... does that method work well enough to show whether the "test transistor" works.... even though the original 23 channel radio MAY NOT have used that part? ( I hope I am making sense...)

Yes. All of the CB finals, AM and SSB, use the same leg configuration. It can be also used for the MRF 477, 497 finals if you know the leg configuration and get the right legs in the right holes, EBC CBE..........Some of the older rigs used a different type of final but again if you know which leg is the base, collector, and emitter and get them in the right hole. This works as a quick go no go test along with a wattmeter. Things get hot in a hurry without a heat sink!
In testing a "real" 2sc2166 will show 4 watts, a fake less than 1 watt.
I have even tested amplifier finals in this. Soldered wires on the tabs and plugged them in. I don't do that anymore as I was at a swap-meet in the San Diego CA area 30~~40 some years ago and bought a 2sc2879 final type tester. It has a single amplifier board with adjustable caps, a cut out for the transistor to be pushed against the heat sink along with Teflon pads to make contact on the transistor connections to the board. It has a mechanism like a re-loader jig to hold it all in place when testing. The adjustable caps make it so it will test all different transistors, MRF455.........2290....It will even test the old stud mounted ones by turning up side down. There is a hole in the ram for the stud to go into. Someone thought this out when it was made. Being in the San Diego area where I bought it I suspect the guy's name was Merit.....

 

[guitar_199]

Yes. All of the CB finals, AM and SSB, use the same leg configuration. It can be also used for the MRF 477, 497 finals if you know the leg configuration and get the right legs in the right holes, EBC CBE..........Some of the older rigs used a different type of final but again if you know which leg is the base, collector, and emitter and get them in the right hole. This works as a quick go no go test along with a wattmeter. Things get hot in a hurry without a heat sink!
In testing a "real" 2sc2166 will show 4 watts, a fake less than 1 watt.
I have even tested amplifier finals in this. Soldered wires on the tabs and plugged them in. I don't do that anymore as I was at a swap-meet in the San Diego CA area 30~~40 some years ago and bought a 2sc2879 final type tester. It has a single amplifier board with adjustable caps, a cut out for the transistor to be pushed against the heat sink along with Teflon pads to make contact on the transistor connections to the board. It has a mechanism like a re-loader jig to hold it all in place when testing. The adjustable caps make it so it will test all different transistors, MRF455.........2290....It will even test the old stud mounted ones by turning up side down. There is a hole in the ram for the stud to go into. Someone thought this out when it was made. Being in the San Diego area where I bought it I suspect the guy's name was Merit.....

THanks much for the reply! I have always thought about using an old radio like that but figured that various finals might all be so "different" that ONE radio wouldn't work to test them all. I guess you are proving that this IS a viable way to test!!!!! Thanks.