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has anyone had a radio built by lesters customs?

your absolutely right the guy who built my cobra always said that its only like 15 watts other guys get 25 out of them, well......they did they died long ago this thing can talk all over the country on 15 watts or maybe its a little more on ssb its funny that thing receives like crazy and if you can hear someone you can talk to them with no amp. ever had one of those radios that werent no power house but just spot on? ive had and still have many radios more powerful than the cobra that simply wont touch the cobra at 15 watts i know that sounds crazy but its true
and something i forgot to mention the talk back for am the cobra has it never squealed ever. you have to back the mic gain down to 1/2 on am. now that lescomm you couldnt even turn it on and if you did while the amp was on you may shatter the truck windows lol
 
your absolutely right the guy who built my cobra always said that its only like 15 watts other guys get 25 out of them, well......they did they died long ago this thing can talk all over the country on 15 watts or maybe its a little more on ssb its funny that thing receives like crazy and if you can hear someone you can talk to them with no amp. ever had one of those radios that werent no power house but just spot on? ive had and still have many radios more powerful than the cobra that simply wont touch the cobra at 15 watts i know that sounds crazy but its true
that little watt meter i have for mobile use forest soldered a resistor that i know of and did some other things but i had to use another part that screwed on for ssb power measuring accuracy and i havent found it yet, i have a special length jumper to compensate when its on there for antenna tuning, i have the jumper i just cant find that other part ?? that meter he redid the ratshack im gona have my girlfriend make a sticker that says that for it lol anyways you would be surprised how accurate this thing is. That meter, the radio, the amp, rk56 mic jumper wires everything he setup as a kit lol i can tell your a knowledgeable radio fan robb i wish we were close enough id show ya and let ya play on it and on the lescomm id almost bet i would hear you say the word wow at some point lol and you would be done with the lescomm pretty quickly it has fingernails on chalkboard level white noise ewwww
 
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that little watt meter i have for mobile use forest soldered a resistor that i know of and did some other things but i had to use another part that screwed on for ssb power measuring accuracy and i havent found it yet, i have a special length jumper to compensate when its on there for antenna tuning, i have the jumper i just cant find that other part ?? that meter he redid the ratshack im gona have my girlfriend make a sticker that says that for it lol anyways you would be surprised how accurate this thing is. That meter, the radio, the amp, rk56 mic jumper wires everything he setup as a kit lol i can tell your a knowledgeable radio fan robb i wish we were close enough id show ya and let ya play on it and on the lescomm id almost bet i would hear you say the word wow at some point lol and you would be done with the lescomm pretty quickly it has fingernails on chalkboard level white noise ewwww
i mean it get all the channels possible without getting rosetta stone lol
 
your absolutely right the guy who built my cobra always said that its only like 15 watts other guys get 25 out of them, well......they did they died long ago this thing can talk all over the country on 15 watts or maybe its a little more on ssb its funny that thing receives like crazy and if you can hear someone you can talk to them with no amp. ever had one of those radios that werent no power house but just spot on? ive had and still have many radios more powerful than the cobra that simply wont touch the cobra at 15 watts i know that sounds crazy but its true
I can attest to the fact that both the skip conditions and the kind of antenna used makes all of the difference. I use a 959 and a four element yagi and NO AMP and can talk everywhere if conditions are really in. Never, ever needed an amp.
 
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I can attest to the fact that both the skip conditions and the kind of antenna used makes all of the difference. I use a 959 and a four element yagi and NO AMP and can talk everywhere if conditions are really in. Never, ever needed an amp.
i dont have a base its always from a car it will do it off a k40 or this wilson 1000 i have now ?
 
i dont have a base its always from a car it will do it off a k40 or this wilson 1000 i have now ?
A 1/4 wavelength - 108 inch steel whip - is still the the unbeatable champ for a mobile antenna even today. But I would run the Wilson 1000 if that is the best you have. I use a RM/Italy Z-180 (equivalent to a Sirio 5000 Performer which is still available today); the extra length it provides over a Wilson 1000 (over a foot longer) is next best thing to a 1/4 wave antenna you will find - IMO . . .
 
A 1/4 wavelength - 108 inch steel whip - is still the the unbeatable champ for a mobile antenna even today.




Not exactly, An antenna analyzer measurement will prove an input impedance around 37 ohms since it is one half of a dipole meaning some current loss at the feed-point since it is being fed with 50 ohm coax.

Also if you understood wavelengths, velocity factors, and antennas like you claim to be an expert audio engineer in another thread, you would know that 108 inches is a bit too long for 11 meters, CB frequencies that is.

An easy fix if you understood antenna matching using a shunt coil and a hacksaw.
 
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Not exactly, An antenna analyzer measurement will prove an input impedance around 37 ohms since it is one half of a dipole meaning some current loss at the feed-point since it is being fed with 50 ohm coax.

Also if you understood wavelengths, velocity factors, and antennas like you claim to be an expert audio engineer in another thread, you would know that 108 inches is a bit too long for 11 meters, CB frequencies that is.

An easy fix if you understood antenna matching using a shunt coil and a hacksaw.
Still sore; eh?
I don't hold grudges, you might want to try that on for a fit.

Yes; 37 ohms is equivalet to roughly an SWR of 1.5. Of course, it must not matter to you that it is a resonant length given as an approximation. In fact, there is nothing wrong with an SWR of 1.5. A resonant dipole also has the same SWR of 1.5 but it is 75 ohms. The 1/4 wave antenna also has a wide bandwith with a flat 1.5 SWR. While not exibiting any positive gain in dB, it also has the best gain of any mobile antenna.

So what?
 
Was strange watching that video, firstly both the stations on 385 and 375 at start are both from my home city Glasgow, I know that accent anywhere.

The guy that made the video doesn't understand AM watts too well, often referred to the carrier as x amount of watts avg rms. you don't get watts rms, you get Avg watts, which comes from the rms of voltage and rms of current multiplied.

20 amp draw is about right for a 140-160w radio depending on bias/amplifier class and wires sufficient to reduce voltage drop to next to nothing. No way is 20 amp going to do 500w, even with 100% efficiency it would struggle around 260w.

108" whip would be ideal and was the length they were always made too allow tuning all over cb band with a bit of trimming. Usually about 104-106" is about right depending on where you centre it.

Normal vswr should be just under 1.4:1 at resonance, about 36 ohms, but there's a few factors in that and may well read higher or lower depending on situation and surrounding materials. A vswr of 1.39:1 is insignificant and adding a lossy shunt coil to tune it out seems self defeating. Will still blow the arse off every 50 ohm mobile made, despite any manufacturers claims of audio gain or shite like that.

a resonant dipole has a slightly higher vswr at 72 ohms in freespace,approx 1.44:1, again no biggie, again dependent on mounting location and surrounding objects. I don't see many rushing out to shunt coil their dipole despite the vswr being worse.

I don't see what claims Robb made you have issue with.

I fail to see the point in custom cb's. if you need it customised you bought the wrong radio, All a good radio should need is a good alignment if its not already aligned well. A half decent export with a rm kl203p will do the job worldwide. And biggest advantage of all is if radio or amp blows you still have the other to use whilst the faulty part is replaced, put both in one case you lose the lot. Plus add extra heat, the biggest enemy of most of these radios for stability.

All that money too murder any advantage you would gain by using a wilson or k40 seems pointless when a sirio or 1/4 wave whip are both cheaper and more efficient than either.
 
I made contact to Magnum357 and Hobie102 from the forums here on 12-15W today, no amp! It can be done! :)


~Cheers~
yes i know on a base antenna especially id like to have a base to play around with i rent this house when i buy one i will have one, id be a tv star here probably lol
 

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