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Vanillagorilla
Intermediate Member
Username: Vanillagorilla

Post Number: 399
Registered: 4-2005


Posted on Wednesday, December 28, 2005 - 10:11 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)


Got another 2 pill Palomar from a friend to use in my base. Decided to replace my dual SRF3775 Pal225 with the dual 1446 Pal300 elite (really just for preamp purposes). All seems to work well EXCEPT the SWRs go WAY up beyond 3 on ANY power range with any variable input from radio. It's NOT from more amp output as the 225 seems to do just as well. Only difference I see in output is the 300 has more of a DK spread in the 3 ranges and more overall swing.
The SWR is usually 1.4 with amp off..2 or under with amp on. New amp kicks that number up quite a bit. Is it the different transisitor package that does that?...yes tried different jumper lengths...yes took another NEW Pal300 out of a box to try...same.
Going to lower the mast to dial the antenna into as flat as possible SWR at center band and try it again but still expect higher than desired SWR from this kicker.
Thoughts?

Thanks,
Hank
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Moonraker
Intermediate Member
Username: Moonraker

Post Number: 123
Registered: 3-2005


Posted on Wednesday, December 28, 2005 - 10:05 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

My palomar does the same thing. I thought I had it fixed by adjusting the antenna, but had only burned up my meter (very, very cheap meter). With the amp off I get 1.3:1, but the swr goes sky high with the amp on. I've been told that the swr reading is false with the amp on because of harmonics. I got tired of messing with it and I just talk on it. It's been running this way for months, I use it for hours at a time and quite often and have had no problems. Now that I've said that, it may blow up tomorrow, but so far so good. I just can't beleive the swr is really that high because it works very well and doesn't get hot.
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Hotwire
Advanced Member
Username: Hotwire

Post Number: 758
Registered: 1-2005
Posted on Wednesday, December 28, 2005 - 10:27 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Now that I think about it I have the Galaxy 225 in my car. With amp off I have 1.1-1.2 swr through the band. Turn the amp on and wham! 2.5-3.0 through the band. Could not fix it and it was this amp only.SWR will swing down with modulation. So I took a chance and been using it for over a year now on high with my 148. Hank you have heard my mobile before. I agree with Moonraker. Must be something like harmonics. I am not saying anything like, " Yo Hank! Go ahead and run that amp with high swr man it will be ok." Just putting in my 10 cents. Watch out for smoke!
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Vanillagorilla
Intermediate Member
Username: Vanillagorilla

Post Number: 400
Registered: 4-2005


Posted on Friday, December 30, 2005 - 9:21 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)


Welp,shame on me :-) Found some pinched coax along the mast going up. Somehow the coax got tied under one of the guy wires and would pinch it against the mast whenever the wind blew N/W. Obviously going on since I raised the mast 10 more feet and pulled this brainless stunt in a hurry. All seems well now. 1.1:1 @ ch20 barefoot and 1.3:1 heat on in any range after a retune of the antron tuning rings for fine tuning.
Ken..yes I have heard your mobile..hundreds of miles away keep it up!
Bottom line over here...I need new coax!

As a sidenote I noticed this 300 acts more like a modulator than a standard linear. Any range seems to DK low then swing high. My 225 mentioned above DK's higher on average and swings less. Hmmmm?
Ahh whatever! Thanks for the input Boys and happy new Year!

Hank
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Taterbug
New member
Username: Taterbug

Post Number: 6
Registered: 12-2005
Posted on Friday, December 30, 2005 - 1:34 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

my palomar two pill acts crazy on my mobile. amp off i have a 1.0-1.1 swr. amp on it blows off the charts. i think moonraker is right about the harmonics because i talk hundreds of miles away when the skip is rolling. never gets warm and i talk for hours.
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Vanillagorilla
Intermediate Member
Username: Vanillagorilla

Post Number: 407
Registered: 4-2005


Posted on Saturday, December 31, 2005 - 7:29 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Further silly notes on this kicker and its SWRs...IF My barefoot readings are BELOW 1.2:1 then they won't rise over 1.3:1 with heat on in any range. Anything over 1.4:1 and hit the heat results in over 3.1:1 SWR. Ordered new 75' run of RG8 from Copper and we'll get it fixed this week.
My output is great when reflected power is down and the amp never heats up BUT with those over 3 SWRs she hits 100+degrees fast and the power drop is near 30%. I'll wait and get the coax...again..thanks for the input!
One more thing...I don't know what kind of input you guys are putting into this particular linear but I found the output to be downright LAME if your not putting at least a 4.5DK into it. I had a 3w DK and it resulted in less than 100w overall even on Hi range. Perhaps these 1446 transistors(90w output @ 5w in) DO IN FACT warrant being called Hi-Drive by stock radio standards. I like to call it MED drive :-)
Drive it with 5 watts and she smokes AND stays cool IF the SWRs are good....just my notes here...not the bible.
I currently set it up on HI and set radio (Delta Force :-))DK to where amp is DKing 60 and swings to 200+(which is a mic gain adjusted 20w swing). Like I mentioned before this ends up being at least a 4.5 to 6w DK.
Always have a little fan on her anyway as a matter of course.

Thoughts? Suggestions? Flames?

3zzzz
Hank
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Patzerozero
Senior Member
Username: Patzerozero

Post Number: 2157
Registered: 7-2004


Posted on Saturday, December 31, 2005 - 10:48 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)



i love 10 ohm smoke...all it means is after you replace your transistors, try 1/4 watt less drive then the last time

i have a power supply at the base DEDICATED for FANS ONLY
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Vanillagorilla
Intermediate Member
Username: Vanillagorilla

Post Number: 411
Registered: 4-2005


Posted on Sunday, January 01, 2006 - 10:13 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

...I like yer attitude Pat

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