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eHam Forums => VHF / UHF => Topic started by: KB6DYA on December 12, 2022, 02:51:42 PM

Title: vhf/uhf amps
Post by: KB6DYA on December 12, 2022, 02:51:42 PM
Who makes the best 100 watt mobile amps for  2 mters, 220, 440, 900 & 1296.
Title: Re: vhf/uhf amps
Post by: K1KIM on December 12, 2022, 04:47:11 PM
I don't know if anyone makes "one" for all those bands.

Google for some reviews.

RM Italy is a place to start.
Title: Re: vhf/uhf amps
Post by: KD7RDZI2 on December 13, 2022, 03:42:54 PM
I don't know if anyone makes "one" for all those bands.

Google for some reviews.

RM Italy is a place to start.

100w beyond 70cm are a lot and rather expensive ... I am afraid that RM-Italy has no amps at those frequencies. Instead of increasing power it might be more efficient to increase the antenna gain.
Title: Re: vhf/uhf amps
Post by: WA3SKN on December 14, 2022, 10:17:27 AM
The "best"???
Q5signal might build you a custom one.  It takes time.

http://q5signal.com/

-Mike.
Title: Re: vhf/uhf amps
Post by: W1VT on December 14, 2022, 11:00:58 AM
A 100W amp for vhf/uhf in many cases, isn't that practical.  HTs could use the power, but they often have weak receivers that can't be fixed.

Mobile rigs have better receivers, but put out too much power for amplifiers and turning down the power may not be easy.
A low power setting may have momentary glitches or power spikes that will damage expensive power transistors.  Fixing that can be a challenge.
Title: Re: vhf/uhf amps
Post by: KG6BRG on December 14, 2022, 05:23:33 PM
https://www.dxengineering.com/search/department/amplifiers/part-type/vhf-uhf-amplifiers
I have a Toptek amp for 2 meter SSB and it's been flawless in performance and has either RF sense or hard line keying, which is a bit hard to find in low drive amps.  They also offer a UHF amp as well.
Title: Re: vhf/uhf amps
Post by: WB2WIK on December 17, 2022, 08:14:48 AM
Who makes the best 100 watt mobile amps for  2 mters, 220, 440, 900 & 1296.

W6PQL makes and sells kits and some fully-built amplifiers at this power level for all these bands.   I wouldn't call them "mobile" amps necessarily, although some might be used that way.
https://w6pql.com/klitzing_amplifiers.htm
Title: Re: vhf/uhf amps
Post by: K1KIM on December 17, 2022, 09:59:48 AM
I have a RM Italy LA145 for VHF and an inexpensive AliExpress Chinese one for UHF I use with my HT's when I want more power portable etc.

The LA145 does SSB and FM.

Both will put out 85W or so when driven with 1.5-2.0 watts. I'm sure both have a bit of splatter, but are acceptable for what they are.
Title: Re: vhf/uhf amps
Post by: KM3F on March 21, 2023, 04:07:39 PM
From experience, I have an ALINCO HT DVXJ-50.
The Rx is equal to a mobile unit.
It drives a 35 watt amplifier or can drive a higher power amplifier if the design is made to accept lower drive to attain the higher power.
You would have to be selectable about what you put together.
Why is the Rx so good?
The HT uses direct conversion and has a sensitivity down to better than .15 uv.
I use this setup as permeant in mobile use with a hand mike
The audio reports are very good without asking.
There is one issue that may be important in some cases.
That is in an area where there are pager transmitters just above 2m in the 150 band, the HT may respond to them from overload if they are of high power.
I had that issue and run it down to a pager.
I built a very deep trap tuned to that interfering frequency, that has a hi Q narrow attenuation notch more than -55 dB down. That solved the interference issue permanently with nearly no through loss from the filter design used.  A band pass filter will not do in these cases.