BC350 Series - double or triple conversion?

[nanZor]

I'm contemplating picking up a new 355N, but I can't seem to determine if these are double or triple-conversion units. I've looked at the manuals, but I don't see any listings for any of the IF frequencies in the specifications starting from the old 350A onwards..

If anyone knows, I'd be grateful.

 

[KD9KSO]

I don't think anyone still makes a dual-conversion scanner.

 

[nanZor]

Well, I'll cut Uniden some slack if the RF deck is a 20 year old carry-over from when the 350A was first introduced and is truly indeed a double-conversion unit.

The series seems popular with the airband-streaming crowd, so perhaps if it is dual conversion, they have good attenuation of the image, and maybe quality bandpass filtering.

Thing is, I'd buy a new 355N tomorrow if I knew the specs, even if it was dual conversion (good engineering can minimize the image problem with image attenuation, plentiful bandpass filtering etc), but making me guess keeps my wallet closed.

 

[GTR8000]

This isn't definitive, however Uniden has traditionally made it very clear in the owner's manuals when a model features triple-conversion. You can find that listed for the BC72XL, BC95XL, BC125AT and the BC75XL. Oddly, the BC125AT lists triple-conversion as a feature, but doesn't provide the IF frequencies, whereas the other three manuals do.

Any mention of triple-conversion or IF frequencies is conspicuously absent from the BC340CRS, BC370CRS, BC355C and BC355N manuals. Take that for what it's worth.

And yes, there are still modern double-conversion scanners manufactured. The aforementioned Uniden clock radio series (340 and 370) are double-conversion, as are (were) the GRE PSR-100, PSR-200 and PSR-200U.

 

[Rt169Radio]

May I ask what double or triple conversion is?

 

[RonnieUSA]

May I ask what double or triple conversion is?

Communications receiver having three different intermediate frequencies to give higher adjacent-channel selectivity and greater image-frequency suppression.

So You want a radio that has triple conversion, it does a better job at rejecting images.

 

[UPMan]

Some info below:
Double Superheterodyne Radio Receiver :: Radio-Electronics.Com
Superheterodyne receiver - Wikipedia, the free encyclopedia

BC355C and BC355N are both triple-conversion receivers.

 

[nanZor]

Good to know the 355C and 355N are triple conversion - thanks for the confirmation UPMan.

Re the 340 and 370CRS, I think they are triple conversion based upon the specs for the Uniden / Radio Shack pro136 rebadge, which actually comes with specs. They list 3 IF frequencies:

265.50-60 mhz, 10.80 mhz, and 450khz.

Although I'm not sure if the 265mhz IF was used for the former tv-audio usage in either up/downconversion, so perhaps they are indeed dual-conversion. I just wish specs were published so I didn't have to guess.

 

[UPMan]

All our models are triple conversion.

 

[GTR8000]

I stand corrected, and happily so. It's nice to know that all of Uniden's current lineup is triple-conversion, although as hertzian points out, it sure would be nice if that was pointed out in all of the user manuals for reference.