[Top] [All Lists]

Re: [TowerTalk] Steppir tuning noise

Subject: Re: [TowerTalk] Steppir tuning noise
Date: Sat, 21 Feb 2004 09:35:56 EST
List-post: <>
In a message dated 2/20/04 9:44:39 PM Eastern Standard Time, writes:
run of the mill steppers (with decent temperature ranges, etc.) are probably
around $50, brand new, in big quantities.  Shielded steppers with the fancy
connectors are more like $500 or $1000.  Fluidmotion would have a hard time
selling $10,000 antennas, and I suspect that folks would balk at spending
dollars/foot for high performance shielded control cables as well.<<

You don't need $500 to put shield over the leads coming from the motor and to 
use shielded cables. We have been doing it for $5 with ignition noises in 
mobile installations where thousands of volts and real sparks are involved. Dog 
food can and piece of braid can do miracles.

Also instead of square wave hard pulses, something closer to a perfect keying 
waveform (or sine wave) might do to minimize the harmonics generation and 
noise way up in the HF frequencies.

Nothing is impossible. I managed to reduce my 28 MHz second harmonics from 
the 14 MHz exciter after going through 2 kW linear, into tribander by 20 dB. 
same helped 10m QRM to Channel 2 TV. Some PI-L filtering, stubs and link 
coupled network can do "miracles". 

It would be interesting to see what steps were taken by SteppIR to reduce the 
noise problem. Is ANY filtering/suppression used?  Again, I do not have their 
antennas, just saw the pictures and judging by the comments. 

73 Yuri,

See:  for "Self Supporting Towers", "Wireless Weather 
Stations", and lot's more.  Call Toll Free, 1-800-333-9041 with any questions 
and ask for Sherman, W2FLA.

TowerTalk mailing list

<Prev in Thread] Current Thread [Next in Thread>