Date: Mon, 25 Apr 2011 16:24:52 -0700
From: Shane Youhouse <kd6vxi@gmail.com>
Subject: Re: [Amps] DIN vs N
PL 259s I've personally witness run at 2Kw carrier, 10 Kw pep.
N's AND BNC's I've seen about 5-6 kw carrier, 100 percent modulated.
LC I've seen go to about 55Kw, modulated.
I've seen the DIN go in the neighborhood of 140Kw input (linear amp, NOT plate
mod xmitter). Estimates put the carrier at around 80.
Putting ANY vswr on these connectors REALLY degrade them. ALSO, I've found
MAKE SURE you don't put the connector where it will be in an installation where
current can soar. Believe it or not, the N and BNC are the WORST for
multiband. I've seen more of them meltdown than I have PL connectors on
multi-band, tuna fed antennas. LOTS more surface area on a PL 259 than a N or
BNC.... Means more current carrying at low freqs and more area for skin effect
at higher freq's. The downside is they are NOT impedance constant, and the
quality REALLY varies on PL \ SO connectors.
Anywho, my unprofessional take on hi power and connections. Feeding yagi's
gets tricky, too.
--Shane
Kilowatt Delta Six Victor Xray India
#### And this all depends on several factor's.....like FREQ, HUMIDITY, is Dow
Corning DC-4 used...and what is the PEAK V across the connector itself. Then
toss in duty cycle, connector brand, install method,was silver solder used,
etc, etc.
## 4:1 swr, such that the peak current is sky high....but duty cycle is low
enough.... probably no big deal on the much bigger pin used on teflon/Silver
PL-259's [ and assuming you also use the mating silver/teflon mating female]
## Now if the peak V is sky high....look out, the uhf connector's will cut
loose on you every time. You hear this from the 11m ops all the time. "1:1
swr, no problems..... 1.3:1 swr...and the connector will flash over"
## Type N is rated at 500 V. 7-16 Din is rated for 2750-2900V. There
is No RF on the pin anyway! Once plugged in, all the RF flows down the
outside of the mating female. You will see that the base of a type N..or 7-16
DIN is bigger OD than the pin itself..and in fact is the same OD as the mating
female.
### a 7-16 din means the OD of the mating female is 7mm [ .284" which is
huge] . The 16mm is the ID of the mating outer conductor collet. The
OD of the pin, on a 7-16 DIN is a big mother... aprx the size of a 22 cal slug.
## 16mm - 7mm = 9 mm. 9mm/2= 4.5mm There is a 4.5mm air gap between
OD of pin , and ID of outer conductor collet on any din. 4.5mm air gap is
good for aprx 2750-2900 v RMS. Add 41% for peak V.
The beauty of the 7-16 DIN is.... it's not much bigger than a UHF connector !
The chassis flange on any 7-16 din is exactly 1.25" square... VS 1" square
for any Type N or SO-239 chassis connector.
## I don't have time nor patience for stuff arcing/flashing over/blowing up
these days...esp at the top of a tower... and worse yet, at the top of a
mast...or way out on the boom..and ditto with remote switch box's, lightning
arrestor's, and anything else.
nothing worse than trying to trbl shoot stuff..... at night, or in the
rain/snow/ice, lousy WX, high winds etc. It's bad enough on a sunny
afternoon. Of course, trbl shooting also implies un-doing all the tedious
vapor warp, wx proofing you just installed b4. Then you might have to take
sveral connectors apart, find the right one, try and fix it....then WX proof
several connectors. Then it will just happen again anyway. IMO, just do it
right the 1st time.
later... Jim VE7RF
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