Search found 96 matches

by COMMENG
Wed Nov 15, 2017 11:03 am
Forum: FM Radio
Topic: FM range question - coastal mountainous terrain
Replies: 22
Views: 744

Re: FM range question - coastal mountainous terrain

Is there some reason you can't move the transmitting facilities to the Nieves Peak area somewhere along GC 134 (such as the San Bernardo refuge) and increase power to 5kW? I concur with Deep Thought, your major problem here is obstructions from volcanic landforms with the resulting wave reflections,...
by COMMENG
Thu Nov 09, 2017 4:29 pm
Forum: From the Trenches
Topic: Your Biggest On Air Screw up..
Replies: 35
Views: 6744

Re: Your Biggest On Air Screw up..

NECRAT wrote:
Thu Nov 09, 2017 3:08 am
COMMENG wrote:
Wed Nov 08, 2017 5:41 pm
College 10 Watt FM station, St. Louis, about 19XX.
See I learned my roman numerals. That would be 1920, sir!

:mrgreen:

Ouch! :mrgreen:
by COMMENG
Wed Nov 08, 2017 5:41 pm
Forum: From the Trenches
Topic: Your Biggest On Air Screw up..
Replies: 35
Views: 6744

Re: Your Biggest On Air Screw up..

College 10 Watt FM station, St. Louis, about 19XX. I was on late at night playing some trash from a music list I despised. Earlier, my girlfriend had called and asked me if I had had a meal yet and I said no. So she said she would bring some pizza over and we could have pizza and a coke (soda pop fo...
by COMMENG
Fri Oct 20, 2017 12:23 pm
Forum: Ask the Engineers
Topic: Wanna Play "Guess What's in the Grey Box?"
Replies: 16
Views: 780

Re: Wanna Play "Guess What's in the Grey Box?"

abwdvm wrote:
Tue Oct 17, 2017 2:13 pm
Taken at a nearby radio station. Going to be my responsibility soon.
No, but why don't you post a schematic with an explanation of the circuitry. :)
by COMMENG
Tue Oct 10, 2017 3:15 pm
Forum: AM Radio
Topic: OMNIA.7AM
Replies: 10
Views: 1162

Re: OMNIA.7AM

We ordered one for a 1kW station and are running with a loaner Omnia.7 AM right now. We are still tweaking for the sound we want. Working with the Intermediate Level tweaks right now. Lots of customization available.

BTW, has anyone read the Specifications sheets for this unit? :D

COMMENG
by COMMENG
Wed Sep 27, 2017 1:58 pm
Forum: AM Radio
Topic: DX-50 works as speaker
Replies: 9
Views: 1020

Re: DX-50 works as speaker

OK, guys, here's the skinny: The output of the variable cap connects to the tank coil ( why do they call it a "tank circuit"? ) via bolted tubing. At full power this point would arc with modulation. I noticed the bolt was literally red hot at 10 kW when I walked int the transmitter room before turn...
by COMMENG
Wed Sep 27, 2017 12:46 pm
Forum: Everything else
Topic: Parts
Replies: 0
Views: 155

Parts

I am not sure if this is the proper Forum but occasionally we see BE's needing parts for various transmitters, bot FM and AM.

A source that seems to have a large inventory of parts for older transmitters, ATU's, etc. is Dennis:

signalsradio.wordpress.com


COMMENG
by COMMENG
Tue Sep 26, 2017 1:35 pm
Forum: Everything else
Topic: FUNCTION GENERATOR
Replies: 2
Views: 212

Re: FUNCTION GENERATOR

I have a circuit that converts those low impedance unbalanced outputs to balanced ports.

Let me know if this interests you.


COMMENG
by COMMENG
Tue Sep 26, 2017 1:28 pm
Forum: FM Radio
Topic: Tower needed
Replies: 3
Views: 373

Re: Tower needed

I would contact this Group: https://natehome.com/ and find out which erector company would be closest to your location. The tower company engineer helps you with permitting, siting, FAA regulations, environmental impact statements, FCC regulations, material procurement, etc. The last time I had towe...
by COMMENG
Mon Sep 18, 2017 8:42 am
Forum: FCC Discussion
Topic: OET: OFFICE OF ENGINEERING AND TECHNOLOGY ANNOUNCES TECHNOLOGICAL ADVISORY COUNCIL (TAC) TECHNICAL INQUIRY INTO REFORM.
Replies: 0
Views: 172

OET: OFFICE OF ENGINEERING AND TECHNOLOGY ANNOUNCES TECHNOLOGICAL ADVISORY COUNCIL (TAC) TECHNICAL INQUIRY INTO REFORM.

"The FCC’s Technological Advisory Council (TAC), an advisory group to the FCC operating under the Federal Advisory Committee Act, is investigating FCC technical regulations and the processes by which they are developed to determine if increased efficiency and decreased regulatory burden can be reali...
by COMMENG
Mon Sep 11, 2017 10:51 am
Forum: FM Radio
Topic: New member - LPFM transmitter recommendations
Replies: 32
Views: 1910

Re: New member - LPFM transmitter recommendations

We have had good luck with the analog FM 250C from BE in a number of stations.

http://www.bdcast.com/information-cente ... ifications

We like to homebrew our own audio chain so we are not interested in internal audio processors.


COMMENG
by COMMENG
Wed Sep 06, 2017 9:10 pm
Forum: Digital Television
Topic: PCR Drift, how does it happen?
Replies: 1
Views: 325

Re: PCR Drift, how does it happen?

These might help: http://pixelmetrix.com/datasheets/AppNote/AN101%20PCR%20Jitter.pdf https://cdn.rohde-schwarz.com/pws/dl_downloads/dl_application/application_notes/7bm55/7BM55_0E.pdf https://www.tek.com/document/technical-brief/laymans-guide-pcr-measurements http://www.tvtechnology.com/media-system...
by COMMENG
Tue Sep 05, 2017 7:38 am
Forum: AM Radio
Topic: DX-50 works as speaker
Replies: 9
Views: 1020

Re: DX-50 works as speaker

I would shut the transmitter down and check two things:
1) the internal arc gap for dust, dirt, gap, etc.
2) the power combiner mother board(s) for dark spots and cracked toroids along the secondary rail rod.

COMMENG
by COMMENG
Tue Aug 08, 2017 12:08 pm
Forum: FM Radio
Topic: Tube question for the experts
Replies: 3
Views: 418

Re: Tube question for the experts

Here are some comparative tube Specifications:

http://www.g8wrb.org/triodes/


COMMENG