[Date Prev][Date Next][Thread Prev][Thread Next] - [Date Index][Thread Index][Author Index]

Re: Any feedback on Mirage KP1-440 Preamp?

Hi Guys,

Well this happens until you modify your set up to prevent it.  Luc is 
taking the best approach with the FT-847 (which is simple to do...and 
almost easy depending on your skill level with a solder iron and hand 
drill).  I modified my FT-847 about 4-5 years ago and have no preamp 
"smokes" since.  Other models of radios may or may not be easy to 
modify for separate Rx antenna connector.  I have planned to put a 
short article on my website showing how to modify the FT-847 (google 
DL4MEA for a good webpage showing how).

Instead of pruchasing an expensive RF switched preamp, you could get 
a coax relay to place in front of your preamp so that it switches to 
bypass in transmit.  You need a second relay to place after the 
preamp if still using a single coax feedline.  Surplus relays can be 
found at hamfest for as little as $10.

It is pretty inexpensive to run a dedicated receive coax out of the 
preamp to your radio.  You can use RG-58 since the preamp gain 
offsets any coax losses (assuming a reasonable run of no more than 
150-feet).  I use better coax on my eme receive line but then I am 
trying to squeeze out every 0.1 of a dB for moonbounce.  The P144VGA 
or P432VGA preamps only cost $79.95.  You can replace the Gasfet in 
them if you are skilled at surface-mount technique, or maybe find a 
local ham that is.  The MGF-1302 GasFet costs about $5.  ARR does 
repair but I do not know what they charge.

73 Ed - KL7UW

At 04:33 AM 4/18/2008, Luc Leblanc wrote:
>On 17 Apr 2008 at 23:13, Mike Ryan wrote:
>Hello all,
>Zapped my ARR RX only preamp for the second time out of stupidity. 
>Time for a switched model. Cant afford the $200+ amps from SSB and such.
>The Mirage seems attractive. Can anyone share their experiences with 
>this model or suggest a differnt affordable preamp? I looked at the
>ARR switched models already. The high powerd mast mount is too much 
>$$ and the low power one only handles 25 watts. I could easily smoke
>that one out of stupidity as well (my rig can do 50 watts).
>Mike WB1AAT
>I beat you with 3 now and one to go. I will make separate RX 
>connector on my FT-847 (Just get parts in a recent Hamfest) as per the already
>available mods. No more preamp use until theses mods.
>The last event a hand mike fell on a CW key...Its fun to see how 
>things can turn bad so quickly! The next steps transistors change-over in
>this micro tiny container so many hours of pleasure to come...:)
>Luc Leblanc VE2DWE
>Skype VE2DWE
>Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author.
>Not an AMSAT-NA member? Join now to support the amateur satellite program!
>Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb

Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author.
Not an AMSAT-NA member? Join now to support the amateur satellite program!
Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb