Avantek amplifiers any good?

hanlonmi06

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I've acquired three Avantek brand amplifiers, but I cannot seem to find any information on them. does anyone here have any insight to these amps, if they are any good for using as a amplifier ahead of a distribution block, or just straight signal amplification?

UTC 21-104M, 10-2000mhz
AMM-1010N, 50-1000mhz
UTC5-211-2, 10-500mhz

Id like to try the UTC 21-104M in front of a blonder tongue 8 way distro block rated 5-1000mhz.
 

prcguy

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I have an old Avantek catalog with some pages missing and the only one I can find is the UTC5-211 with 38dB gain, 3.5dB NF and +14dBm IP1. You don't want to use that as a receive amplifier. The UTC 21-104 is probably a similar low level amp with mediocre NF and a low IP1. I suspect the AMM is a larger higher power amp with high NF.

These amps were probably made in the 80s and you can get much better specs these days for not much $$.
 

hanlonmi06

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Well that's a bummer! What sort of applications would they have been used in back in those days?

I think I've seen you (or perhaps Ubb?) recommend different amps, whats your favorite family or model of amps for something like feeding a distro block?
 

dlwtrunked

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I've acquired three Avantek brand amplifiers, but I cannot seem to find any information on them. does anyone here have any insight to these amps, if they are any good for using as a amplifier ahead of a distribution block, or just straight signal amplification?

UTC 21-104M, 10-2000mhz
AMM-1010N, 50-1000mhz
UTC5-211-2, 10-500mhz

Id like to try the UTC 21-104M in front of a blonder tongue 8 way distro block rated 5-1000mhz.
The catalog page prc guy refers to can be found at
 

prcguy

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When I worked at Hughes Aircraft in the 80s and 90s building microwave transmitters and receivers for use in radar cross section imaging I used hundreds of Avantek amplifiers from VHF through 90GHz. Certain models are good for receiver front ends, others for receiver and transmitter IFs, some for transmitter PA drivers and some for transmitter PAs.

The UTC 21-104 might be used in transmitter or receiver IF or for general lab use raising weak signals so they can be measured on test equipment. It could have been used as a broad band receiver front end where you have control over what the receiver sees, like inside an anechoic chamber where it would not get overloaded by off air signals.

An amplifier for feeding a VHF/UHF scanner or receiver should have a low noise figure and a 1dB compression point and IP3 spec high enough so it doesn't get overloaded and create IMD from being hit with strong TV, FM broadcast and cell phone tower stuff. In my area its a big problem and most preamps fail miserably. If your area is not too bad with strong signals you might get by with a Minicircuits ZX60-P103LN. The only thing I don't like about that amp, besides not working well here is its gain slope where its got about 22dB gain in the VHF range, 18dB gain in the UHF range and about 14dB gain in the 800MHz range. That slope should be opposite to make up for higher feedline losses at higher frequencies.

For me the Minicircuits ZHL-1010 is working well but its got a trade off of higher noise figure for higher overload characteristics. Its also got about 10dB of gain which is what I needed and if you are feeding something like an 8-way divider there is a 20dB gain version. Whatever you use you want to attenuate the output of the amp so your overall gain is small like 0 to maybe 4dB. If the amplifier gain is too high its going to reach a problem area with overload sooner than a similar amp with less gain.

Well that's a bummer! What sort of applications would they have been used in back in those days?

I think I've seen you (or perhaps Ubb?) recommend different amps, whats your favorite family or model of amps for something like feeding a distro block?
 
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hanlonmi06

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dlwtrunked - thanks for the info. Sometimes when I've done searches and found myself on some datasheet pages, it seems like every "pdf" link is a link to something else, so I probably gave up to quick.

prcguy - thanks for sharing your thoughts on the Aventek's. Seems like things have probably come a very very long way since the 80s and 90s. 90GHz, that seems impossibly high in frequency for back then! Ill check out the minicircuits models as well, thanks again!
 

dlwtrunked

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I know too well about be strung on to find info. One of my favorite places to compare for pre-amps if one has the money (caveat: usually $100-$200 range so one better be careful in knowing what one is doing):
 

Ubbe

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That slope should be opposite to make up for higher feedline losses at higher frequencies.
Wouldn't it be an easy modification to insert a 3,3pF capacitor inline, scrape off the copper foil on the input of the amp and solder it there or put it inside a metal box with connectors? That value has a 50 ohm reactance at 800Mhz and 500 ohm at 100Mhz, a possible 10dB reduction at VHF. It would be an additional 6dB at 25Mhz but probably not a problem, or use 4,7pF for a more moderate slope.

/Ubbe
 
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