Some years ago I noticed an advert in QST by the purveyor of a soundcard
interface that claimed it could allow FSK RTTY through your soundcard! Of
course this was AFSK and clearly, the advert took advantage of newer, less
experienced hams.
I called Steve Ford, WB8IMY, the Managing Editor of QST who immediately grasped
the scam. The ads were never again seen in QST. The League is still on watch
for false advertising. I am not sure there is similar attention in any
Canadian publication but none of my VE friends like wool pulled over his eyes.
I hope this gets reported.
Mike W4AAW
Sent from my Verizon 4G LTE Smartphone
----- Reply message -----
From: "Jim Thomson" <jim.thom@telus.net>
To: <towertalk@contesting.com>
Subject: [TowerTalk] What am I missing....balun
Date: Fri, Feb 17, 2017 2:51 AM
Date: Fri, 17 Feb 2017 01:16:01 -0500
From: "Bert Almemo" <balmemo@sympatico.ca>
To: <john@kk9a.com>, <towertalk@contesting.com>
Subject: Re: [TowerTalk] What am I missing....balun
...and this device (choke) would give you over 30 dB attenuation from 1 to
30 MHz!! I'm definetely missing something!! How can this kind of advertising
be allowed? I'm no expert but I've made a few chokes and never managed to
accomplish this kind of choking impedance with a couple of turns of coax
through a few toroids. Can someone explain please! Thanks
Bert, VE3NR
## Its 30 db or more of return loss. IE: swr is flat across the spectrum.
The marker freq is set to 26.980 mhz. I suspect its optimized for the
11m QRO crowd. It might just be type 43 and not type 31 cores used, dunno.
33.13 db return loss = 1.045 : 1 swr
## add all the turns you want, and you still wont be able to get it to work
from 1.8 to 30 mhz.
## Interesting to note his 10 kw cw, 20 kw pep 1.8 to 30 mhz version
uses 4 turns of 393 coax through 4 x type 31 cores. RS is 3.2 k
from 13-28 mhz. His 3.5-60 mhz version uses 4 turns through
just 3 cores. On both these 2 version, the cores are all type 31.
## I saw what some of the 11m ops use for their version of a bead balun.
They used 20-40 type 31 or type 43 2.4 inch OD torroid cores slid over .875
heliax.
To get the .875 inch heliax or LMR-1200DB to work on a yagi, they mount the
yagi
way up the mast, with a 3 turn loop around the mast, large diam loop, like 3-4
ft
across, and below the yagi. The 1.4 inch ID cores are only .5 inch thick, so
they gotta
use a lot of them. Ceases to amaze me what folks come up with.
Jim VE7RF
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|