Pre 78 700/800MHz amplifier

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kmartin

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I was wondering if anyone has tested one of these or has thoughts on this New preamplifier ? It's pricey but was wondering how well it performs ?
 

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Silent Key
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It should perform well if that's what you really need. It won't make up for a poor antenna or installation. If you're trying to overcome simulcast distortion it could make it worse. What are you trying to accomplish?

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prcguy

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Its pricy because it has bypass relays inside so when you remove power it switches the preamp out of circuit and lets the unamplified signals pass through. Otherwise the specs are not that impressive. If you just need a preamp and no filtering or relays this one is only $40 and the specs are much better. I just put one in the front end of a 900MHz repeater and its working very well. Mini-Circuits

I was wondering if anyone has tested one of these or has thoughts on this New preamplifier ? It's pricey but was wondering how well it performs ?
 

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Silent Key
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Its pricy because it has bypass relays inside so when you remove power it switches the preamp out of circuit and lets the unamplified signals pass through. Otherwise the specs are not that impressive. If you just need a preamp and no filtering or relays this one is only $40 and the specs are much better. I just put one in the front end of a 900MHz repeater and its working very well. Mini-Circuits

I don't see insertion loss mentioned in the specs for the Mini-Circuit LNA.
 

KevinC

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I don't see insertion loss mentioned in the specs for the Mini-Circuit LNA.

I'm not the sharpest tool in the shed, but I'd "think" any insertion loss in an amplified circuit would be negated by the amplifier gain...but I could be wrong.
 

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Silent Key
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I'm not the sharpest tool in the shed, but I'd "think" any insertion loss in an amplified circuit would be negated by the amplifier gain...but I could be wrong.

I would think any loss within the preamp would result in some loss of signal to amplify to begin with before the receiver.
 

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Silent Key
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Silent Key
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Something wrong with your fingers? ;o)

$120

I've been looking/searching and was unable to find it, otherwise I wouldn't not have ask. And most people would link a source to an response, but I guess that would have been asking too much. :rolleyes:
 

Ubbe

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It's got a frequency range of 740-860MHz and if that sits at the input then the noise figure of 3,5dB might be unterstandable when there's a couple of dB loss in the filter but then the IP3 of only 24,4dBm at a 20dB gain seems really bad. Why do they put so low quality components in a $180 device?

/Ubbe
 

Ubbe

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Buddrousa, have you ever tested modern TV junk and configured it correctly with a zero or very moderate system gain? Or did you go directly to Stridsberg as you though that high cost must equal high perfomance? Stridsberg has easy to use plug&play devices that everyone can use but you get higher performance at 1/3 of the cost if you use low noise 0,5dB NF and 40dBm IP3 amplifiers connected to CATV splitters, if you can connect coaxes yourself between the different devices.

If you can connect scanners to a Stridsberg multicoupler you should also be able to connect scanners to a splitter and then the splitter to the amplifier and then power it from a USB cable. No special skills needed other than ordering coaxes with the correct connectors and getting splitters that have the appropriate attenuation.

/Ubbe
 

buddrousa

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Yes I have a HP Service Monitor for a long time I used junk because I was CHEAP then I started using QUALITY EQUIPMENT I got my DEGREE in 1979 and passed my 2 class General Radio Telephone License also in 1979. I also work parttime in a KENWOOD 2WAY RADIO SHOP.
 

rolesen

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For those that have the Stridsberg Model Pre-78 PreAmp, how does it perform if you are on the fringe of a particular P25 site?
 
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