Schottky Receive Modification on a Cobra 29 LTD

[SMILEX2692002]

I was thinking about buying a Cobra 29 LTD with an RFX-75 installed from DTB radio.
Is the Schottky receive modification he offers really worth the extra money?

I would only be using the radio in my shack, not as a mobile.
Noise levels are very low on my Imax 2000 and Sirio D-27 horizontal dipole antenna at my qth.

I was always one to believe the better the antenna the better your receive.

 

[9C1Driver]

DTB does good work, Doug at custom cb radio is probably the best out there with RFX installs. You will be happy with either.

The receive mods when done right with a proper alignment work great. You are correct, the antenna system is most important. A 300 dollar radio on a 15 dollar antenna will loose to a 15 dollar radio on a 300 dollar antenna

Why not do the mod AND run the best antenna you can?

 

[SMILEX2692002]

I have never used DTB radio before. From what I read on other topics on this forum DTB seems to be one of the better companies to do business with.

 

[RADIOOMAN]

A good antenna is definitely the way to go, but most every cobra 29 I've ever tuned would do 30 -32 watts pep on a Bird meter.
I wouldn't spend more than a minute to just do a little bit more than double my power.
I don't know how much you are spending to have a 75 watt radio but I think you could spend less money and have 150 to 200 watts pep with a small 2-pill amp.
That will have the desired effect on the other guys Smeter.

 

[SMILEX2692002]

Not everyone wants to run a external amp.

Back to topic.
Has anyone on the forum had a component upgrade in the receiver section of there radio that really made a difference?
I have used all different kinds of radios over the years and have never had any components in the receiver section upgraded.
Is this just smoke and mirrors?
Do the component upgrades really make a difference?

 

[KG6YGE]

I'm wondering the same thing, so have ordered the low capitance detector diodes and a lower NF RF first stage amp. I should have my results in a couple of weeks. Mine is a Realistic 458.

A couple of other factors, besides these, are at play. One is the background environmental noise at 11 meters. There are times of the day when I connect the antenna, and the hiss on the channel increases, meaning that the noise I just added to the radio is greater than the intermally generated noise of the radio itself. There are other times (no squelch, RF gain at max) when connecing the antenna results in no further background hiss from the speaker. This means that the radio could benefit from the mods, possibly. This does not enhance selectivity, just overall sensitivty.

Then there is the PLL controlled LO, which after mixing with the incoming, results in the PLL tracking noise (and the base oscillator phase noise). Although this effects FM systems more than AM.

Then there is the fact that CB rigs don't employ pre-selectors, meaning that the whoie 500 KHz CB band is amplified by the first stage. If your antenna is really resonant at the center of the 11 meter banc, that itself is an exterrnal band pass filter (pre-selecter).

 

[The Jerk]

You will not be disappointed with DTB's work, he is one of the best.