
Bartholomew, would love to hear your answer on this.

Moderators: genlock, sportsvoice
The Commish generally asks for this diagram (with values) when they do a technical inspection.genlock wrote:Have one of them make a diagram of the tuning stuff so it can be lost like the last one was.
Grab a salesperson and have them point in the general-direction of one of your stations' transmitter sites.genlock wrote:You see, radio is not just the glamor, sex and money at the studio,
Real intellectual work is done by engineers in the field.
Rock wrote:Well, it's...complicated.
Here's it in a nutshell.
1) AM tuning blew capacitor. blew capacitor so badly there was no way to determine value. Contract Engineer called our buddy, another Engineer, and asked him to bring bridge so they could re-tune. also bring extra caps, since we've been spitting in the wind to find the proper one. Contract engineer, like EVERY BLOODY ENGINEER I KNOW has his vehicle bed stacked with posthole diggers, 3 rolls of audio wire, 6 bags of quikrete, ladders, antennas, etc. In his passenger seat is a 700 piece craftsman tool kit, 3 starguide receivers, 3 years of back-issues of Radio World, 2 desktop PCs, and a set of keys that would be more adequately used in the Dark Ages as a Flail. In other words, an absolutely AWESOME Engineer.So, since he has no room, and buddy awesome engineer hisself is coming to have his vehicle serviced in-town, needs a ride to the stick site.
2) Which is why, at 10am yesterday morning, I was standing on Greenbrier Mountain, watching 2 dudes take readings, put in cap, measure readings, curse loudly and vociferously, replace cap. This went on for many hours...the sun was warm, and the wind was enough to draw my nads into my high intestine. I was very cold.
I learned many things yesterday....
Bees love RF. Any kind of enclosure near a stick, box, or dish...they'll be there. And pissed.
Capacitors in parallel work kind of like resistors in series. I did not know this...having learned this, I feel no sense of accomplishment.
I still have no frakking clue what they were doing, even though they tried to 'splain it.
Good Engineers rule...modern day Sorcerers.
Next time, I clean out the dude's truck. I don't need to do that again.
genlock wrote:Cheap and quick, yes.
Might be able to get you back on till a suitable replacement was found.
Would that capacitor be stable in differing temperature and humidity?
I don't think so. Great geek solution.
Most general managers would love it and would not order the correct replacement.
Maybe till it blew during the Friday night Football game.
That's EXACTLY what they told me...I just couldn't remember all of it. ok...any of it...oldtvman2 wrote:capacitors in parallel add and the voltage stays the same. when matching the antenna it dosen't matter how many cap you use what matters is that you have a match. when using several capacitors you have a greater chance of one breaking down. and changing the match. with the antenna matched and the transmitter having the proper output current everything should be ok. if the antenna is not matched then the pattern could be greater or less depending on the match. dc blocking usually isn't a concern at the antenna. in the old days the transmitter engineer knew the values in his tuning unit. but then we had engineers at the transmitter and full time at the station, not contract engineers. bees like tuning units because there is a certain ammount of heat generated and they like that. have had to use a lot of wasp spray when checking base current readings. also their nest can change the tuning of the antenna.