Connecting an oscilloscope to your CB radio transmitter output.

in this video I describe two different methods for connecting up your oscilloscope to your transceiver for testing.
PLEASE NOTE THAT I MADE AN ERROR ON THE VALUE OF THE RESISTORS. THEY ARE ALL 100 OHM RESISTORS.

[@13EL121]

Many thanks Darek! 👍 Fantastic video. Helps me lot.

[@GroundControl204]

Great video, waving from my test bench. 73 👋🏻

[@UDX-21]

Thanks for this! I wanted see how you did it- I hit the like and other buttons. Happy Thanksgiving from 21 S.C.

[@DerekHerbst747]

I'm glad you found it useful. Thanks for the kind words. Happy Thanksgiving from France!

[@UDX-21]

@@DerekHerbst747 10-4

[@gerhardvanwykzs4rum685]

Baie dankie vir die informasie

[@barbsblogs1563]

Thanks for sharing am I right in saying this could a way of setting up the deviation and also I guess you could use this method for a sniffer pick up for a frequency counter?

[@DerekHerbst747]

Yes you can do that too if you have a deviation meter for FM

[@brianbloom1799]

Hi Derek Do you by anychance live in the Us, and do radio repair.

[@BaldurNorddahl]

Won't that coupling be frequency dependant? If you use the digital scope you could run FFT to check the harmonics. Or use TinySA. But I expect the higher harmonics to be attunated due to the coupling.

[@DerekHerbst747]

Yes you are right. However this method is only used to view the envelope, so as to check the biasing of the final stage. Under or over biasing will result in distortion of the audio. SSB modulation is particularly important to check using this simple method. I use a spectrum analyser to check harmonic and spurious emissions. You can't see harmonics on the scope.

[@BaldurNorddahl]

@@DerekHerbst747 I use a spectrum analyser too, but for someone who does not have one, the FFT function on the digital scope should be able to do something. As alternative to the wire spool around the dummy load, I think one could also just use a BNC T-adapter to route the signal via the scope before terminating in the dummy load. The scope has a 1M ohm input and will not create too much reflection if connected directly to the T-adapter.

[@sniperchaz111]

Very nice equipment unfortunatly i couldnt afford something as sophisticated just a cheap pocket sized osciloscope a frequency counter ohms meter an antique signal generator which is so old im too scared to plug it in lol and a few different atus with built in dummy loads swr and power meters upto 3kw nothing in comparison to that test gear lol

[@DerekHerbst747]

Actually, my Stabilocks can only handle 50 watts continuous.. of course other than that they're great tools!

[@johnnyshades2743]

Would love to learn to fix CB and HAM radios. I have an basic understanding of electronics but where can I learn?

[@DerekHerbst747]

Start with normal FM radios and learn how to fix just receivers. You'll be surprised how quickly you learn, and how much great information is available on the Tube.. Check out "Electronics old and new". My buddy Manuel makes excellent videos!!

[@mexico3459]

Easy go to a tafe school or university they run many electronics courses that's made to fit your experience from starter to advanced because if you want a career in that field you will need a certification I did one their great fun and you learn so much good luck my friend 🙂

[@jankomuzykant1844]

If I understand correctly, you connected 4 resistors in parallel (47R/4) then again 4 resistors in parallel (total 8 pcs) and those two sections in serial ? Then you end with 2*(47R/4)=23,5R resistor 🤔

[@DerekHerbst747]

My mistake: the resistors are 100 ohm.

[@Thefreakyfreek]

@@DerekHerbst7473:35 Somone needs to do Thier homework 😂 I'm sorry mate noting personally

[@theDaftman]

@@DerekHerbst747 yes, i just ran the maths as in the video because i know it was wrong, before commenting i just looked to see it anyone else had spotted the discrepancy.

[@terryshrives8322]

Ok man, come on. Other then that fancy equipment, what else can we just buy for up to 1000 watts to put in between the scope and radio?

[@DerekHerbst747]

You can use the method described in the video. Just use higher wattage resistors to cope with the power output. Alternatively you can buy a 1000 watt dummy load with a tapping for a scope output. Some RF wattmeters also have an attenuated output for station monitoring.

[@terryshrives8322]

@@DerekHerbst747 ik thats really helpful, I appreciate that so much. Thank you

[@pottypete5593]

​@@DerekHerbst747 Hello . Cool video. Could i wrap wire around my 25 watt dummyload heatsink ? Then connect probe to wire ?

[@DerekHerbst747]

@@pottypete5593 it might work

[@pottypete5593]

@@DerekHerbst747 thanks will give it a go :)

[@JamesBronson-hy3rb]

Lol 🤣 back to the bench

[@frankbaron1608]

simple. either use a decent attenuator or stick an antenna wiith matching imedance in the osciloscope input