Quoting Paul Luggar [email protected]:

I suggested a preamp on a handheld would possibly overload the front end of the radio as my Kenwood THD7E overloads with the arrow when I go hilltopping with it. With a preamp and local conditions in the UK it would be useless, "If" RF conditions are super quiet then it may be ok but why preamp with

such a short feeder?

Paul: While it's often stated that a mast-mounted preamp helps to overcome the losses in feedline, the low-noise preamp's advantages go beyond that. In this case, if the preamp has a lower noise figure than that of the first stage of the HT, a more sensitive overall receiving system will result. This increased sensitivity comes at the loss of some dynamic range, however. On the whole, in low signal work, we need to aggressively reduce local noise anyway to hear the signal, with or without preamp, so the trade-off is a good one for us.

73, VE9QRP

I agree. ARR seems to be the cream of the crop when it comes to the preamps that I have used. The ARR works great with my satellite work.

I also have used a preamp with my arrow for portable work. It does not overload the HT / Scanner and is great because you don't have to be "on point" with the arrow. In fact, with a good pass, I have been known to set the arrow down on the hood of my truck and still get a great signal. Good luck!

73,

Paul KB3NDS

On 5/9/07, Armour, Randy (ITS) [email protected] wrote:

I plan to purchase an ARR SP-432VDG preamp at Dayton Hamfest. Mirage offers the KP-1-440 preamp with similar specifications. Does anyone on the list have advice on which unit to choose?

Thanks in advance,

Randy KI4LMR

-----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of John W Lee Sent: Thursday, May 03, 2007 7:42 PM To: [email protected] Cc: [email protected] Subject: [amsat-bb] Re: Preamp

Jeff, An ARR SP-432VDG would work just fine with that setup. I have two of those preamps and they work great!

I've done many portable operations with an HT and Arrow with great success.

I saw a message saying this would overload the HT. Not true. But your friend will be able to HEAR and hear well.

73, John K6YK _______________________________________________ Sent via [email protected]. 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

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Sent via [email protected]. 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

Ditto here. Same experience. Either an ARR or an SSB Electronics.

73, John - K8OCL/5

----Original Message Follows---- From: "Chad Wasinger" [email protected] To: "Armour, Randy (ITS)" [email protected] CC: [email protected] Subject: [amsat-bb] Re: Preamp Date: Wed, 9 May 2007 06:36:50 -0500

Hi Randy,

The SP-432VDG is a great preamp, I've used one for satellites and weak signal for many years. I personally wouldn't purchase a mirage, never had one, but haven't heard much good on them.

Also, SSB Electronics have an excellent line of preamps: http://www.ssbusa.com

I use their 2 meter mast mount for weak signal and EME, works great.

Good Luck, Chad N0YK

----- Original Message ----- From: "Armour, Randy (ITS)" [email protected] Cc: [email protected] Sent: Wednesday, May 09, 2007 12:35 AM Subject: [amsat-bb] Re: Preamp

I plan to purchase an ARR SP-432VDG preamp at Dayton Hamfest. Mirage offers the KP-1-440 preamp with similar specifications. Does anyone on the list have advice on which unit to choose?

Thanks in advance,

Randy KI4LMR

-----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of John W Lee Sent: Thursday, May 03, 2007 7:42 PM To: [email protected] Cc: [email protected] Subject: [amsat-bb] Re: Preamp

Jeff, An ARR SP-432VDG would work just fine with that setup. I have two of those preamps and they work great!

I've done many portable operations with an HT and Arrow with great success.

I saw a message saying this would overload the HT. Not true. But your friend will be able to HEAR and hear well.

73, John K6YK _______________________________________________ Sent via [email protected]. 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 [email protected]. 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 [email protected]. 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

Many thanks to everyone who offered advice on a preamp solution. I never expected to quickly receive so many clear and concise replies. This list is monitored by many people willing to share their experience and expertise. Your opinions are surely appreciated!

Randy - KI4LMR

-----Original Message----- From: Stefan Wagener [mailto:[email protected]] Sent: Wednesday, May 09, 2007 9:36 AM To: [email protected]; [email protected]; Armour, Randy (ITS) Cc: [email protected] Subject: RE: [amsat-bb] Re: Preamp

SSB Preamps!

I am running them at -40 in the winter (Manitoba) and during the hot summer. Very low noise, adjustable amplification, rock solid for outside use. Best I ever had and I tested a few. Have three and they work beautiful with the FT-847 and the TS-2000X on 2 m, 70 cm and 23 cm on 70+ feet of cable.

Highly recommended.

Stefan , VE4NSA

Michael,

At 01:59 PM 5/9/2007, Michael Wolthuis wrote:

Well, now that it is summer in MI I finally am installing a full new satellite setup, but the preamps have always confused me and I am looking for help to get it right once and for all.

Well spring is just starting here and the frost is not out of the ground but starting to see a little green. Leaves should be out in a couple weeks.

All the latest conversation shows I should get ARR or SSB preamps. My question is two-fold:

1. Which models of each for UHF/VHF? (do I need the mast mount type

so I can put them outside, or can I put them inside a small weatherproof enclosure)?

Actually, your choice. Wx proof cost more. buying a sandwich box to use is cheaper.

More importantly: 2)I am confused by Bias T's, Power Injectors, vs just running 12volts of a power supply up to the small tripod and connecting it to the preamps.

I prefer running power separate from the coax. Cheaper, simpler, more fool-proof.

From what I can tell I need preamps that sense transmit and receive since I will be likely transmitting and receiving on such things as PCSAT on the same freq. So it needs to pick that up remotely on the coax? So, with that said I would imagine that is the RF Switched version of the ARR preamps. Then, I am just down to how do I power them? It seems to me that putting both the UHF and VHF preamp in a waterproof enclosure and then running 12volt power to them makes sense, but if I could power them via Coax that would be easier to do in the setup.

I believe you can buy an RF-sensing preamp with either power up the coax or with external power and T/R control line. I do not like using RF sensing T/R switching since in CW or SSB the relays are constantly switching back an forth. Relays will fail faster this way.

One can buy a plain preamp, run four-wire cable and use a coax relay to switch between Tx line and preamp. I prefer to run separate Tx and Rx coax lines to the shack, but you can add another coax relay between the preamp and your TS-2000 to use a common coax.

Probably cheaper to buy the preamp with internal switching. Beware that some models only rated to 25w power.

The radio is a TS-2000x if that helps.

I have a FT-847 so not enough familiar to advise on the TS-2000; both can power preamps thru the coax.

Whatever your choice, mount the preamp at the antenna for best low-noise performance. At 144 MHz you might get away with the preamp in the shack; at 432 MHz you will sacrifice several dB of noise factor; at 2400 MHz you will hear little to nothing with a preamp and converter in the shack.

73, Ed - KL7UW ====================================== BP40IQ 50-MHz - 10-GHz www.kl7uw.com 144-EME: FT-847, mgf-1801, 4x-xpol-20, 185w DUBUS Magazine USA Rep [email protected] ======================================