[amsat-bb] Re: Have a TS-2000 and wonder if the Flex or a Icom-9100 , mm

MM ka1rrw at yahoo.com
Mon Feb 22 06:32:54 PST 2010

My concerns about the Icom IC-9100 are as follows:

When you add HF to a satellite radio you reduce the performance of the satellite bands.  What we want for Satellite, EME and DX Terrestrial is a very high performance VHF/UHF receiver, with excellent sensitivity and selectivity.  We do not need or want HF in a VHF/UHF DX radio. A good satellite radio should not contain HF.

IC-9100 Receiver is only a Double Conversion, (better than the 910 which is a single conversion)

IC-9100 TX power output is too high for 2-meter and 70cm for satellite work.  
2-meters 100 watts,  70cm 75 watts.

Let me explain:  
For serious Terrestrial DX and EME you need to run more than 100 watts.  The output level of the 9100 is too high to match most solid-state and tube amplifiers.  
Most VHF/UHF amps are designed for 25 or 50 watts maximum input.  Since the IC-9100 puts out 100 watts you will eventually forget to set you TX power level and you will destroy your external amplifier.

The manufactures of Transceivers and Amplifies need to agree upon a set of standard power level so the amplifiers and transceiver can be properly matched without worrying about destroying the amplifiers.

Suggested standards for VHF/UHF bases stations:
 6 Meters 50 watts
 2 Meters 25 watts
 70 cm	25 watts
 900 mc	10 watts
 1.2 gig	10 watts

External Preamps:  
Again for serious DX and satellite work, most use very high quality external pre-amps.  The Icom IC-910 required Icom externals pre-amps to compensate for the Single conversion receiver.  The Icom preamps did work, however there specifications (Gain 15 dB 2-meters) were not as good as other external third party pre-amplifiers (20-25 db 2-Meters), and they were also limited to 100 watts of RF.  It is not known if the Ic-9100 will also required similar Icom external Preamps.

Dated Design:
The design of the IC-910 was dated when it went into production.  The IC-9100 has built-in DSP and a few more bands, however it is still out of date for what the EME/Satellite/DX community needs for this century.

IC-9100 Potential Good features:
Built in IF-DSP (32 big and 24bid ADC)

What do we want for this century for Terrestrial DX, EME and Satellite:

Dedicated TX and RX for VHF and UHF.
Digital filters (similar to a Ic-756 pro III and newer radios)
Band Scope.
TX power to match external amplifiers.
RX Quad conversion receiver.
Full USB computer control (Not RS-232, Not TTL, Interface must include memory channels with the Repeater off-set bit, which is usually omitted by Icom)
Satellite mode knob 100% Identical to the Satellite mode knob on the Yaesu 736R.

My ideal rig would look like the Icom IC-756 Pro III.
It would not contain any HF.
The whole RX and TX system including digital filters would be designed just for the following bands:

6 Meters 50 watts
 2 Meters 25 watts
70 cm	25 watts
900 mc	10 watts
1.2 gig	10 watts

Additional RX/TX filters for satellite reception.

It would also have the Satellite Mode switch of the Yaesu 736R, placed in a similar location on the Rig.
Multiple Line level audio outputs for computer interfacing to support digital modes such as JT65 and other modes.

Just my wish list.

wf1f Miles


--- On Sun, 2/21/10, Jack KZ4USA <videorov at verizon.net> wrote:

> From: Jack KZ4USA <videorov at verizon.net>
> Subject: [amsat-bb] Have a TS-2000 and wonder if the Flex or a Icom-9100 would be the next best step for satellite work.
> To: amsat-bb at amsat.org
> Date: Sunday, February 21, 2010, 11:36 PM
> Jack 
> Bradenton, Florida
> _______________________________________________
> Sent via AMSAT-BB at 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


More information about the AMSAT-BB mailing list