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here's a weird one....

W

Whiplash-265

Active Member
Aug 14, 2011
280
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Ontario, Canada
my uncle has a 2995dx, which is in an upstairs bedroom...
8x leading out a window to an a99 that is sitting on a tripod (due to BS housing restrictions). coax (approx. 50 foot) is choked at feedpoint with 5 turns on a 4" piece of white abs/pvc

now, here's what's f'd up :)
when he keys he's getting so much rfi (i'm assuming it's rfi) that his Magic Bullet turns on in his kitchen which is thru two walls and approx 20 feet away (prob more like 30'). coax reads true on a 259B and his antenna reads 1.1 @ 27.555

wtf??? ya i've heard about throwing shyt at speakers etc but to actually activate a wired device?
 

I used to do a light show with my nephew's touch lamp. It was also fun to tell him "you suck" through his guitar amp when he played his Ibanez. Put a filter and some ferrite beads on, and the fun went away. lol

73,
RT307
 
How much % modulation on AM? Did he check AM Modulation with an external meter? Should be less than 100%; more like 95%/peak. Did it have the limiter removed/NPC mod? Bleeds/TVI on SSB too? No ground plane on the antenna? Power supply/radio grounded to the house ground?
Just for starters . . .
 
Last edited:
Whiplash-265 said:
my uncle has a 2995dx, which is in an upstairs bedroom...
8x leading out a window to an a99 that is sitting on a tripod (due to BS housing restrictions). coax (approx. 50 foot) is choked at feedpoint with 5 turns on a 4" piece of white abs/pvc

now, here's what's f'd up :)
when he keys he's getting so much rfi (i'm assuming it's rfi) that his Magic Bullet turns on in his kitchen which is thru two walls and approx 20 feet away (prob more like 30'). coax reads true on a 259B and his antenna reads 1.1 @ 27.555

wtf??? ya i've heard about throwing shyt at speakers etc but to actually activate a wired device?
Click to expand...

is the tripod on the roof or the ground ? the lower a antenna is the closer it's proximity to electronics to effect them . what is his 2995 dead keying and swinging ? over-modulating and harmonics from pushing the finals too hard can cause issues too .
 
you cannot isolate an endfed antenna without some form of radials for return currents,
adding a coax choke or w2du balun even a very good one + isolating the mast won't stop cm currents on the coax, kirchoff's equal current law won't allow it to work, voltage will rise across the choke untill kirchhoff is happy and you have rf on the coax outer braid,

here is what has worked for us on a99 and imax to cure the rfi issues you describe,
we have used as few as two 1/4wave wire radials when real radials were not available and that worked too,

good luck.

isolatedimax-1.jpg
 
he's running rf gain full out...and likes to kick up the power mic as well (which is when it apparently causes the "issue"). i'll try and get my meter on it and check the swing (he only ever uses ssb) the radio internal meter shows 150w but who knows how reliable that is lol

PS is internal, has been updated to the newer one, unsure of mods besides the 11m
no gpk and tripod is on the ground...if i can get the mic away from him i think i'll snip a wire or two ;)
 
I've got one of these radios in the shop right now. They have two 2290 output transistors in them and can put out ~160 wastts of fairly clean power if the radio has been properly tuned up.

I think Booty made a fair point, and so did bob85. Having the antenna really close to the shack AND having no ground planes/'counterpoise' on the antenna is going to be the major causes - and they will need to be dealt with. Over-modulation is also a big deal too. So is not having the radio grounded to the house and eventually to the ground rod. Getting a low pass filter will help out too.

Food for thought . . .
 
Robb said:
I've got one of these radios in the shop right now. They have two 2290 output transistors in them and can put out ~160 wastts of fairly clean power if the radio has been properly tuned up.

I think Booty made a fair point, and so did bob85. Having the antenna really close to the shack AND having no ground planes/'counterpoise' on the antenna is going to be the major causes - and they will need to be dealt with. Over-modulation is also a big deal too. So is not having the radio grounded to the house and eventually to the ground rod. Getting a low pass filter will help out too.

Food for thought . . .
Click to expand...

I've seen one of those radios do 350w pure dirty audiiiiooooo

Sent from my Xoom using Tapatalk 2
 
have your unc whip up some margaritas every time the bullet is running...in no time at all your troubles will be over, until the hangover.(y)
 
gamegetter said:
have your unc whip up some margaritas every time the bullet is running...in no time at all your troubles will be over, until the hangover.(y)
Click to expand...

LOL

No idea about the tune Robb :( And definitely appreciate Boots n bob's input and suggestions (sorry bob missed your post as it was made 'bout the same time as mine), will look into your suggestions seriously. Ground rod etc is outta the question, it's a rental. We originally had the whip predominantly even with the roof line but he got "the letter of discouragement" and down she came. Alternatives are in the works :)
 

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