Linear Amplifier Theory Part II, Tank Output circuits and Tuning

Рет қаралды 2,418

7 ай бұрын

Пікірлер: 29

@markrix 7 ай бұрын

My dad was an old ham and id always ask him to explain how he would peak n tune my little cb radios, he would just do it for me, all good info, so much makes sense now. RIP pops.

@tramdr 7 ай бұрын

My Dad used to fix TV's and at one time had a TV shop. Made decent money but people kept breaking into the shop, so he got a job at the factory. Once I got into CB'ing he tried to fix mine when they went out, but that was beyond him. Hence, I started studying electronics and learned to fix them myself.

@stahpit1971 7 ай бұрын

Thanks for the video. Anyone getting into using amps should watch this video.

@tramdr 7 ай бұрын

Thanks.

@kgsalvage6306 7 ай бұрын

Great explanation! I just recently got into RF. Been working on audio for 40 years +. Need to expand my knowledge. This seems like the place to be. Thanks for the great info!

@tramdr 6 ай бұрын

Thanks and welcome I don't really work on audio, but my home audio system is my happy place.

@Mister22x2 7 ай бұрын

Very well done. Straight up is where I've always suggested started. Been a heck since 1983. Do your work brother. It's helpful to the younger hobbiests

@tramdr 7 ай бұрын

Thanks

@321CatboxWA 7 ай бұрын

Well done. Looking forward to the next one. Thank you.

@johntracy9398 7 ай бұрын

Back in the 1960s I use to hang out in the Univ. of Mo. Amateur Radio Shack. At that time they had an older Collins rig from the 1940s as well as more modern gear for the time like the Drake TR-4. One night one of the members was listening to some CBers yammer away with the Collins tuned to the 11M band. Someone decided to play a trick on them and connected the Collins transmitter to the 1000W linear amp. and loaded it to the 10M beam antenna on the roof. When the transmitter was keyed on it created quite the uproar. "Did you hear that? What the h*ll was that? It sure was load." In those days most Hams were not very happy about losing the 11M band to the CBers.

@tramdr 7 ай бұрын

Collins made some great stuff.

@bblod4896 7 ай бұрын

Fantastic lecture. Thank you.

@tramdr 7 ай бұрын

You're most welcome!

@Joe-KN4IFI 7 ай бұрын

A nice straight forward basic operation of tube amplification. Great job Tram Doctor explaining how to uses and trouble shoot an amp. I have an SB-200 that has a fault. Its a strange one. In bypass I have low SWR between the radio and amp and amp to antenna. In operation I have a low SWR between radio and amp and amp and antenna. But no watts out. In standby I get 50 watts from the radio to the antenna. Amp in operation I loose most of that 50 watts from the radio in the amp. Cleaned the relay, nothing. Replaced the relay, nothing. Swapped out tubes, nothing. I have the proper high voltage and filament voltage. Tubes light. I must have a break somewhere in the chain. When I key the amp the tubes do not cherry. But yet the SWR is fine between the amp and radio with the amp in standby or operation. Not sure whats going on. 73 Joe

@tramdr 7 ай бұрын

When keyed up, there is no way to measure the SWR between the amp and antenna if the amp is not putting out any watts when keyed. The SB-200 has a single meter that can read plate Volts, Plate Current, and Grid Current. Using the readings from that should help trace where the problem may lie. Make a vid showing all the meter readings and then maybe I could help.

@keithweiss7899 7 ай бұрын

Very nice Doc! Thank you!

@55weirdharold 7 ай бұрын

Very informative. Thanks !

@tramdr 7 ай бұрын

Glad it was helpful!

@keyboarderror1 7 ай бұрын

You could hear the inrush buzz as you switched on the Dentron. I guess they all do that. A couple hundred amps for a split second charging the caps and testing component integrity,

@tramdr 7 ай бұрын

You are correct. Many of the better built amps have soft start. Dentron's do not. Dentron's do the watts, but IMHO, just like Heathkits, they are no frills, no extra's, just very basic amps.

@MM0IMC 7 ай бұрын

6:42 Sometimes you just have to experiment, as the apps, programmes and book are just a starting point. Been there, done that. 😉

@tramdr 7 ай бұрын

and there are other small variables in the equation too, but again, I am trying to keep it simple.

@thesquirrelchroniclesakare7808 7 ай бұрын

Very informative!

@tramdr 7 ай бұрын

Glad you liked it

@simionlynch8317 5 ай бұрын

Thank you that"s really help full for me .73s...

@tramdr 5 ай бұрын

Glad to help

@bucketofguts 7 ай бұрын

Why a foot switch Doc? Thank you as always.

@tramdr 7 ай бұрын

Most CB amps, especially the small to mid size ones, have an internal keying circuit. The internal circuit in the amp senses the RF coming in from the radio when the radio is keyed and then keys the amp up. Ham amps don't have an internal keying circuit. They have a Jack on the rear that is connected to the amps keying relay. When the output of that keying relay Jack is grounded, the Amps relay is keyed. Some Ham radios have an internal circuit that hooks to the amp's keying Jack so that when the Ham radio is keyed, the circuit in the radio keys the Ham amp up. Very few CB radios have that internal keying out line, so it is common for a CB'er to use a foot switch to key up a Ham amp. The foot switch is connected from the Amps keying Jack and Ground and when you hit the footswitch, it keys the amp up. Some people sell a CB accessory that keys up the amp automatically when the radio keys and some people get that instead of using a foot switch.

@bucketofguts 7 ай бұрын

Thank you Sir!