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 51 
 on: Today at 12:46:43 PM 
Started by EI2GLB - Last post by K1VSK
What about the digi ambivalent readers? We can read too.

 52 
 on: Today at 12:41:01 PM 
Started by EI2GLB - Last post by KD6KVL
The breakdown from EU vs NA is pretty big!  They must be MUCH more needed out east.
Frank KG6N

 53 
 on: Today at 12:32:35 PM 
Started by EI2GLB - Last post by EI2GLB
Just looking over the Stats for the recent activation of the EI DX club from V26

And for you Digi mode haters it makes good reading,

CW and SSB both manage to edge FT8/4 that has to be a first in a long time for a multi Op expedition,

I know V26 isn't exactly rare DX but that doesn't seem to matter these day, people are just hungry to work any DX doesn't matter how rare it is,

Great job by the guys considering how many other expeditions were on at the same time, I didn't see too many reports of pile up's walking over each other,


 54 
 on: Today at 12:16:58 PM 
Started by VE3VEE - Last post by KE4YD
Received OA1F 6 meter FT8 via LOTW
Also received via mail 3W1T 10 meter FT8
73,
David KE4YD

 55 
 on: Today at 12:05:39 PM 
Started by VK4WTN - Last post by N0GV
Updated plots:




Probably easier to view on your browser.

Grover

 56 
 on: Today at 11:30:45 AM 
Started by WB5OXQ - Last post by W9IQ
In addition to Shane's guidance, consider that a 1.1 volt drop with 40 amps of current only requires 27.5 milliohms of resistance. That isn't a lot of resistance! Fuse holders, butt connectors, lug connectors, wire resistance, etc. can all significantly contribute to this paltry resistance.

When I had to power gear in the back of my XL Yukon, I installed an SLA battery aside the gear and powered the battery off the 10 amp auxiliary power connector in the back of the Yukon. The battery very successfully supplied the current peaks yet it fully recharged from the 10 amp circuit due to my relatively low transmit duty cycle.

A bank of super-capacitors can also be used for peak shaving. But they require support circuitry to properly implement so it usually isn't a matter of simply paralleling them across the DC bus.

- Glenn W9IQ

 57 
 on: Today at 10:55:42 AM 
Started by WB9LUR - Last post by KD6KVL
Lets take it further, if you hear the DX, you should get a card....I mean, your heard them....Everyone gets a trophy!  Or, delete all the hard entities because its not "fair".
DX equity for all.  Each to his needs and not to his accomplishments.  Work ethic is privilidge and not all have it.  We should take from those who have and distribute to those who don't, regardless of effort.
Frank KG6N Comrades.

 58 
 on: Today at 10:30:05 AM 
Started by VE3VEE - Last post by KM4SII
Details   KM4SII   JG8NQJ/JD1   2023-04-02 21:19:15   15M   CW   21.04640   MINAMI TORISHIMA

ATNO for me! #279 worked / #263 confirmed via LOTW.

Heard VK9WX this morning on 20m, and he was hearing me, so I was hoping to work 2 ATNOs within 24 hours, but alas, he did not call me before he faded away. Maybe next time!

 59 
 on: Today at 10:17:42 AM 
Started by VE7AXU - Last post by KD6VXI
Myself, I use LMR400.

At my disposal, I have LMR240, LMR 400 and LMR600.  I also have CommScope 1 5/8 heliax.

The tradeoff with ease of use, cheap connectors, ease to bend to come off the tower, etc. vs dB loss made it a no brainer.

Belden 9913 is just fine, if you get it made by someone who KNOWS what they are doing and they use recently manufactured coax.  As someone who was burned a couple decades ago, I won't use it again.  However, I know many that have (civilian and military....  Incidentally, military air comms at 2xx mhx use LMR400...  I installed a system 2 years ago before moving to the island at Edwards) and report no issue.

If I was purchasing all new, and had to buy from a distributor, it would be Davis RF, hands down.  His Buryflex is as good as anything else on the market, is priced at lower prices and will stand head to head with anything LMR or 99xx.



My vote is LMR400 or Buryflex 400.

--Shane
WP2ASS / ex KD6VXI

 60 
 on: Today at 10:11:40 AM 
Started by WB5OXQ - Last post by KD6VXI
I am using a RM Italy HLA 300+ amplifier mobile and it works well and I get great signal reports most of the time. This model does have filters for each band automatically switched. My question would a stiffening capacitor on the amplifier power input improve peak power.  The voltage at the amplifier would be 14.1 volts but drops to 13 volts on ssb voice peaks.  4 gage wire direct to the battery powers the Ft891 and the amplifier.  My antenna is a Tarheel 75A with a 30 inch rod and a capacity hat on top.  This works better and uses less of the coil on any band compared with the 6' whip.

Disclaimer:  I have, and can, operate legal limit mobile.  I've also set up mobiles bigger.

You need to find out what the voltage is at the alternator.

You need to find out what type of charging system your car has.  Depending on the vehicle charging system you may or may not want to run a beefed up alternator wire.

Case in point.  My old 77 GMC 4x4.  Had a #10 wire from the alternator to the battery.  I would drop serious voltage anything over 100 watts.

Changed that one wire out and added a wire from the negative terminal of the battery to the body and frame, and one to the alternator mount.

Solid 13.8 volts, keyed down.  14.4ish key up (it would run near 14 volts constant without the station running).  That was a 4 x 2879 amplifier and IIRC a 70A alternator (or 65 maybe????).

OTOH, 16 x 2879s, 2 x 165A leece neville alternators, a deep cycle and a standard car battery run just fine at 14.4 volts, key down.

My point is, if the voltage is dropping at the battery, then nothing you do at the amplifier is going to help.  If the vehicle electric system isn't up to the task of your amplifier (if it's doing 300 watts, it's pulling 600, that's 50ish amps peak, itself) and if the alternator isn't up to the task, if the wiring from the alternator to the battery group isn't good enough.... Etc.

Find the voltage drop at the car battery.  If it's dropping there, fix that problem first.  But make sure you have a charging system where you can just throw larger wire at it, because not every system is capable of doing that.

--Shane
WP2ASS / ex KD6VXI

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