Years ago I recall somebody on the Part15 Community Radio forum (now defunct) had devised a method of tuning their elevated AM1000Rangemaster from the ground by utilizing some kind of little pulley/cable contraption..
Now not sure why that would be so beneficial, since you generally only have to tune it once and then leave it alone.
I suspect it was really used to turn the power up and down --
Does this ring a bell for anybody?
But they had also ran a wire down and connected to a meter, so that in their studio it displayed the current the xmtr power output.
Now that's neat to me, and it seems like a simple thing to do.
Well, I gotta thing for analog VU meters, always have. I want to get 3 or 4 analog meters and set them up in a nice cosmetic manner, to display things like transmitter power output, mic output, phone patch audio output, and music output... But not sure if I'm thinking about this correctly.. seems correct, but until the equipment actually gets here to be set up, it's unclear to me how these meters would be tied in.
Does this make sense, or is this just something I'm visualizing incorrectly?
Granted, it's not an important factor, it's just an ambiance thing to me.
I always loved the VU meters. My grandfather was (or at least claimed to be) the first licensed ham operator in the state of Tennessee. I used to talk to people around the world on his equipment using his call letters: W4AMBQ. Used to love to watch them meters bounce, there was something magical about them.
I want some VU meters in my studio!
Always a good idea since you can catch it if things change or break but it would need to be done carefully. Pay attention to the loading any meter would place on the transmitter circuitry. Generally, DVMs have an input resistance of 10 Megaohms but analog meters do not. Analog meters are specified with a "sensitivity" such as 20,000 ohms per volt. This means that if a meter is configured to read 10 Volts full scale then the resistance it presents to the circuit is 10 V x 20,000 ohms/volt = 200,000 ohms. The question is will this adversely affect the circuit? It may or may not.
You should pursue this and I mention some of the technical aspects so you won't give up if your try doesn't work. It can be done and it will be worth the effort but it may take a bit of supporting electronics such as I mention below.
I also prefer analog VU meters to the digital, maybe because this is what I "grew up" using. I have an analog VU meter connected to my audio chain so I can set/monitor the audio levels but it required some amplification to get it to work. I used a LM386 amplifier chip and a wall wart supply to get the audio line signal up to a level which drives the meter. With this scheme I can mix the R and L channels for the meter. The circuit includes a pot for calibration and diode limiting in case I do something which would peg the needle.
For AM, I use this meter and for FM I use the LED indicators on a Nanocompressor. I prefer the analog meter.
Here's a neat link you will probably enjoy:
http://www.darkwood.demon.co.uk/PC/meter.html
He used to have a "classic" analog meter but I didn't see it in a quick look at his site. Maybe he removed it or I just didn't see it but he still offers many very nice tools and meters for audio work.
Neil
You have brought back to me a memory of a tremendous AM transmitter I made just after high school.
I was working around professional people and situations, and got a lot of help, so built a transmitter with a big variac on the final tube so I could turn it up until there were blue and orange colors, everything metered with inexpensive little meters from somewhere.
AC power voltmeter, Ampmeter; DC Power to the B+ and filament power; AND a grid-dip meter! Now I wouldn't have a clue how to do that.
I only had that transmitter on (1630kHz PRIOR to the extended AM band) for about an hour because I walked two miles east and it was still just as strong as at the house, so I got scared and dis-mantled it. Music was played on a Wollensak tape recorder.
Fast forward to now and, YES, meters on everything would be great!
Carl, your story reminds me of when I was building a 25 watt AM transmitter for a college carrier current station. It is rumored that this may have been connected to an antenna for brief tests. I won't confirm nor deny.
Back to meters, analog meters have a distinct advantage over digital meters for routine monitoring and adjustment because once the operator becomes familiar with the meter positions it is very easy to quickly detect an abnormal reading. The 250 watt repeater I built and managed had four meters, B+, grid drive current, reflected power, and plate current. I could tell at a glance when entering the shed if anything was amiss such as an antenna problem or the final tube going flat.
I hope Rich pursues this and keeps us posted on his adventures.
Neil
Remote tuning of the antenna would be very benificial. Managing our City's TIS station, I have to check and adjust our antenna when the weather changes. I would guess that electrically short antennas like our Part 15 antennas are affected more than full length antennas. The TIS antenna is only 10 feet long.
Right now with several inches of snow around the base of the antenna, the SWR went from 1.4:1 up to 4.5:1; not good. Fortunately it's a flat roof and I can adjust the antenna off a step ladder.
I'm not sure how the person you mention did it with rope and pulleys.
I'm not sure how the person you mention did it with rope and pulleys.
I would assume it was just a little wire cable and pulley system.. I don't remember who did it, I just recall the discussion. I'm kind of surprised no one else here recalls it.
I just tried going to the "wayback machine" to find it, but it says "We're sorry, access to http://communityradio.com/ has been blocked by the site owner via robots.txt. "
That's the same thing it says when I try to pull up my old site wtyb.com, I could still pull it up about 6 - 8 months ago, but evidently whoever bought it didn't wan't my old site accesible - I assume it was WTYB in Savannah.
Oh! Got sidetracked and forgot what I was going to post here!
Just wanted to mention how surprised I am on the market value of the old used VU meters. Even the cheap tiny plastic ones pulled from old tape decks and such are asking $10 & $15 each, and then they want to add $9 shipping to it! Get real.
There are some brand new one available online for only a couple bucks w/ free shipping, but I was really hoping for some a little larger, but they don't seem to be very common.
And those some of old attractive ham radio vu meters? Not cheap, some even in the $200-$300 range - for one meter!
I ended up grabbing a this http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=170582983873 to play around with It is "Buy it now" for $7.50 & 1.25 shipping. Dual Audio VU Meters and a single Video level meter Set that came from a JVC BR-7000 Video recorder.. He has a bunch of them if anyone is interested.
Now these here are real attractive:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=140483047527
$8.50 + 5.95 shipping.. but I didn't buy any, at least not yet, I'm done spending for awhile. For now I'll just experiment with what I have coming.
Was able to find only 1 or 2 Milliwatt meters - priced too high.. I'm thinking of maybe just maybe printing out a milliwatt scale on adhesive paper and putting it inside over a multimeter face, and some how making that look good inside a studio.. I don't know! - Will mess with stuff like that later during spare time.
Well, that's my update on that project - haven't done nuttin'!
A quick search brought up a meter-scale drawing program.
Here is the link to a METER-SCALE DRAWING PROGRAM.
One is FREE, the more advanced program is $35.
Wow Bob, that's pretty impressive! I downloaded the free version and will toy with it later. Sure beats trying to do something like that with photoshop or something.
From looking at the screenshot examples I didn't see a method of doing specifically a milliwatt meter, but I assume it can be done.
I'll install and toy with the program later.
Looks really cool!