Shocking! No.. transmitting...

You're close enough to the Procaster than when you grab the mic you're acting as an antenna, OR you have a connection somewhere in the mic, mixer, computer, etc where the outside of the mic isn't at ground, and you're bleeding RF into the mic when you grab it. Weird things like this can happen when you're near RF, even Procaster level RF.   It might be sneaking in through a ground loop someplace, lots of possibilities.  In certain rare circumstances I can pick up my Procaster in my production board -- and it's not connected to anything used for broadcasting. But when things are in just the right position, or I grab just the right thing, I can hear RF bleed through!  Try a different mic and see what happens, or if you have changeable mic cords, swap it out for another one. 

Tim in Bovey

Iron Range Country

Tim's explanation is probably right so I have nothing to add except a humorous (I thought so) adventure with a "hot" microphone".

It was back in the early '80s and I was invited to speak at a meeting of the American Academy of Pediatrics on the topic of electrical safety in the intensive care unit. Since this was a medical meeting the planners thought it a good idea to have a nurse present the topic with the engineer (me). The nurse, Linda, a very bright person, and I planned the talk so there would be complimentary comments from each of us, hers being from the nursing perspective and mine from the technical side.

Before the meeting I was doing a microphone sound check and noticed a slight feeling of vibration as I touched the mic. and I recognized this as a tip-off that the mic. might not be properly grounded. In fact, this was one of the symptoms of a dangerous situation that was part of the talk. I talked to the AV guy and he said they floated their sound equipment because grounding it would produce hum. I neglected to tell Linda about this.

So, during the presentation Linda and I were standing in front of an infant incubator which was grounded through the power cord. After I spoke Linda took the mic. and began her part of the presentation. She backed against the incubator and apparently felt a jolt to her posterior and exclaimed "What did you do?" while looking at me. I didn't respond since I hadn't yet figured out what had happened. She backed into the incubator again and yelled "Stop it!". The laughter from the audience of some 400 persons made me realize that it was thought by all that I had done something improper with my hands involving Linda's posterior. When I realized what had happened, I took advantage of the "teachable moment" and explained to Linda and the audience what had happened because of the ungrounded microphone and the shock hazard thereby produced. More laughter, but I bet all remembered that lesson. I am certain that Linda did.

Linda and I remained good friends thereafter.

Neil

I hope that audio guy did something to fix the ground to keep others from being falsely accused of grabbing.

And yes, there is a reason most radio stations, even low power operations, keep the transmitter/tower way off somewhere away from the studio.

I worked at a 5kW with a transmitter in the same building as the studio, and worse, next door to a church.

The station came in on the church's P.A. system and on telephone lines for a mile around.

If you get near a transmitting antenna, you couple capacitively with the antenna and become part of the circuit.

Got to move things apart. Including women who back into incubators.

interesting.

that might also explain the "slight vibration" i get from my mic.

Reading sound forums on "getting rid of hum" they all suggested floating ground.. since the audio boards I have don't have a ground lug.. it was sort of that way out of the box.

guess i need to find a way to ground them 🙂

The hardware store has a grounding clamp that safely grips to a cold water pipe.

I do not recommend grounding to

telephone system ground

cable system ground

gas pipe

drain pipe

hot water pipe.

If you have metal duct work it might be grounded to the electrical ground, that might be another option.

the ground isnt the issue; its finding a place on the mixers.. 

the yamaha is the worst.. it had a hi impact plastic casing.. 

Those Yamaha mixers used to be metal!  I have one about 13 years old or so, it looks the same as my newer one, but the panel is metal rather than plastic!  Some of them have a ground screw on the back.  Does the book have any suggestions on grounding?  They used to include grouding as part of the set up. 

Might be an idea to check and see if your power outlet grounds are really grounds, too.  Sometimes they're not! Theoretically gear with 3 prong plugs will get at least basic grounding through the outlet, but bad outlets, bad installations, bad replacements over the years, bad power strip, etc can lead to a no ground situation.

Tim in Bovey

Iron Range Country

And that is the delima I face on a daily basis. My house was built for the Navy guys stationed at Moffat Field... they were searching for "Jap subs off tha coast-a californyuh" back in the 40s and 50s. Yeah.. they were still looking in the early 50s...

SO.. the wiring is iffy. I think I have ripped most of the aluminum out, but now im working in the garage, which I didn't care about before.. cause its always been a martial arts studio.. now that I have radio crap in it.. i care 🙂

Actually.. I am thinking of just collecting all the stuff I need over the next 2 years, till I retire, then set up the awesome station when we move back to the Beautiful South (tm).

Then, at least I'll have everything stoked up, boxed and ready for installtion.

Today I drove a street that I never use, since it went to a place I usually don't go.

My station was on the radio, and I expected it to fade out in about two blocks.

But after six blocks I suddenly realized I WAS STILL HEARiNG IT!

Whoa. I have a LOBE and one heck of a lobe that I didn't know I had.

Turn back the forum to the time when I couldn't get an AM signal to go uphill a mere 100-feet to the end of the backyard. That problem was solved by burying one long ground radial the whole length, and now the signal reaches the top of the hill.

But what I learned today is that the signal doesn't stop there, it keeps going for maybe a mile or more.

Did you know a directional pattern can be achieved depending on where the ground radials are located? I've never read anything like that that I can remember.

And previously I was certain that a single ground radial wire would put the strongest result on either side of the wire, the same as a high horizontal antenna wire, but apparantly not.

The strong reception was in the direction the ground wire points, not on its sides.

If we have discovered a principle, it might be this: point ground radials in the desired directions and skimp on ground radials in un-desired directions.

You might just get the pattern of your dreams.

Ever put a 102 inch CB whip on the back corner of your vehicle for your CB radio?  Same effect.  You get great signal, receive and transmit, off the opposite front corner of the vehicle.

I'll break here and let someone else inform you that your unbalanced radial would be counted as a long radiating ground wire.

Yes, I learned awhile back that my "mulch-pile booster wire" was an unbalanced radial, and my "to do list" says I should fix it, but I'm glad I learned this lesson about how radials actually work.

I'll have a crew come over and fix the situation before the FCC re-opens.

Wouldn't one long radio be a counterpoise? Perhaps not.

I seem to have a "hot spot" too.  When I leave the house and head out of town (this town is only half a mile long) I have very  good coverage for maybe 3/4 of a mile.  As I head up the hill on the highway out of town, get over the top and maybe a quarter mile along the gisnal fades fast -- can still hear it with a ton of static --and then disappears.  But about a mile or so down the highway (I should really measure it and actually pull over and figure where I am in relation to everything) I hit a hot spot that gives me a loud, clear booming signal for maybe a second or two (at 65 mph) then it's gone.  It happens every day when I drive to town, so it's not some astronomical fluke.

I don't have any radials. I'm grounded to the water pipe where the city service enters the house. 

I really do ned to take a closer look at that.

Tim in Bovey

Iron Range Country

I am guessing, Tim in Bovey, that the water-line you use for ground leaves the house and points in the exact direction where you pick up the hot spot.

To have hot spots in other directions all you need is to have more water pipes coming from those directions!

My second station is grounded to a water pipe, but doesn't reach very far in any direction.

About 1/2 mile from my station, we would get to

a down town area with lots of buildings and stores,

the town hall, etc.

My station would come way way up on the car radio.

I could take my trusty Grundig S-350 (a radio which fell down

my front steps - brick front steps and had nothing go wrong)

- set it on a picnic table in "Blue Back Square," and hear the station

with about 80 percent signal, 20 percent noise.  (Maybe better than that?)

I think all of the big new buildings - built there several years

ago - all were grounded very well.  I think somehow a huge ground

return was helping the signal increase.

Interestingly, the station would fade down at street intersections.

(Reradiating (?) power lines would cross each other at the

intersections and cancel each other out, I think.

I really enjoyed putting in the ground system.  (Add radials

and watch the coverage grow.)  I ended up with 16 radials, some

ten feet and some 20 feet.  (I guess I've said that too many times.)

DOGRADIO 1690 kHz never had a circular coverage area.  It was

just lobes going out all over the place.  Facinating, really.  The

coverage area changed a lot.  The ground would get wet which helped -

but rain would untune my loading coil - which didn't help.

If you decide to make a radial system I would try to chalk it down

on the ground first if you are able.  It's very hard to put

down radials "on the fly" and know where you've been and

haven't been.  (I say that as a general suggestion to any

readers out there.)

Also, the signal would appear in strange places, and then

follow a street for a few blocks and then disappear.

I had a friend drive through town - in one side and out

the other side.  I remember him saying, "Are you sure

this is legal?" - after hearing the signal go down a long

road for a mile or so.  But then, again, he was listening

on a very  sensitive car radio.

I had to turn off 1690 for personal reasons.  The AM

current experiment after that was a blast.

Some of the greatest times I've ever had.

Keep trying different things and have fun.

Bruce, DOGRADIO

P.S. Sorry about the weird line spacing -

I'm having problems here.