Uniden BC75XLT Receives Upper HF

[simpilo]

Typically because it's a Uniden scanner it qualifies for the Uniden Tavern section here at Radio Reference. Since It receives also the last 5MHZ of upper HF It also fits here in the HF section. I have had the chance to record it receiving Sporadic-E condtions on 27.025MHZ AM and 25MHZ WWV Ft. Collins, Colorado. I tweeted the short recordings here:

https://twitter.com/i/web/status/1171009937230761987

https://twitter.com/i/web/status/1171087089045331970

 

[iMONITOR]

I'm surprised. I didn't think too many scanners would do well at those frequencies. What are you using for an antenna?

 

[ka3jjz]

A lot of scanners have this capability; apart from 10 meter hams and CB there's very little in this range, particularly as the solar cycle is so crappy. The 26 Mhz band *used* to have a few broadcasters there (HCJB, way back when, had a QRP operation there at one time), but that's largely been abandoned.

 

[simpilo]

I'm surprised. I didn't think too many scanners would do well at those frequencies. What are you using for an antenna?

10 foot of wire is the magic number.

 

[simpilo]

A lot of scanners have this capability; apart from 10 meter hams and CB there's very little in this range, particularly as the solar cycle is so crappy. The 26 Mhz band *used* to have a few broadcasters there (HCJB, way back when, had a QRP operation there at one time), but that's largely been abandoned.

Thats why I wait on the band to open up. I already have a few shortwave radios but the scanner does a decent job for what it is on the right antenna. There is a local crowd here in Oklahoma City active everyday. Still waiting to hear the 10m ham repeaters.

 

[ka3jjz]

There's a lot of sideband (which no scanner can handle), CW and digital (ditto) - so about the only hams you'll hear apart from the FM repeaters are anyone running AM. Shame no scanner has a BFO...Mike

 

[simpilo]

It would be nice if they added a BFO at least to hear the SSB transmissions. Just as long as it doesn't get to overloaded. I wouldn't mind having a separate 455khz BFO to inject a signal at the beginning of the I.F. chain as long as that signal isn't to big or to weak. Adjustable per signal signal strength to minimize distortion.

 

[iMONITOR]

The AOR AR8200 Mark III B has USB/LSB.

AOR AR8200 Mark III B Wideband Receiver ar-8200

 

[nanZor]

Nice catch!

Even though you can't pick up ssb/cw, what you can do is program a custom search in either AM or FM even though we know it won't work. But what it will do in many instances is start to make your squelch start squawking when there is a strong signal opening. Then you jump over to a rig that does ssb/cw.

Set your squelch as low as you can make it without opening. Program the whole spectrum, or in and around spot frequencies in both am/fm modes and then start scanning.

This "squelch squawker" makes for a cheap band-opening monitor. At least strong enough to break squelch.

Rat-Tail: Try the experiment again, but use a 10 foot long rat-tail attached to the bnc shell and see if there is any improvement. Since you are battery powered from a tiny scanner, all you have as a counterpoise is the dinky circuit-board.

If a long 10 foot rat-tail is cumbersome, you can "linear load" it. That is, run 5 feet out away from the scanner with the wire attached to the shell. Anchor it 5 feet away, and run the rest back towards the scanner, say an inch or three spacing from the wire run, but leave the end of the wire not attached to anything. You could even "center" this technique by running outwards, back towards the scanner and beyond, and then back towards the scanner again - still with the end not connected to anything. Moxon got me into folded counterpoises.

Thanks for sharing that test!