Scanner for 6.25KHz analog FM?

[KG4GUF]

I can't comment to what the scanners do but it seems to me you have used 2 ham radios to try and receive something commercial. Have you tried a commercial radio yet?

That's why I'm asking. I wouldn't know exactly which one to buy, which ones have the capabilities I'm looking for. Originally this topic was in the General Scanning Discussion.

 

[RRR]

That's why I'm asking. I wouldn't know exactly which one to buy, which ones have the capabilities I'm looking for. Originally this topic was in the General Scanning Discussion.

If you are hearing what is truly a 6.25 VHF voice signal, you are hearing NXDN digital.
Analog doesn't work like you claim in 6.25. Either you have an adjustment issue, a setting, or are mistaken what you are seeing, but it's not happening. I don't even know of any commercially available radios that will operate on Analog at 6.25. If so, please post it for us all to see. Of course, in NXDN digital it will, of course in digital mode, but that's about it.
Hell, it just manages to work on analog at 12.5. We lost range when we went from 25 to 12.5 analog. But then we actually gained it back when we went to 6.25 NXDN.

 

[Ubbe]

Are there any radios out there that can handle this narrower bandwidth for FM audio? Thank you!

Any radio or scanner that can do shortwave could probably be set to a more narrow FM bandwidth.

Sometimes it can be an easy operation to replace a 12,5KHz filter with a more narrow one, but the squelch operation will probably be affected so could need adjustment internally if there's no front panel squelch controller.

The US version of IC-V8000 has a NFM mode setting that uses a CFWS450HT filter +/-3KHz wide, so I guess that you do not have that version.

FT-8800 have a CFWM450G filter for NFM that are a +/-4,5KHz filter and can be replaced by a H version that are +/-3KHz wide.

Replacing filters will need some soldering skills. Easiest way are probably to cut the trace going to the filters input and output and solder some wires to the copper traces. It might even work to just connect a more narrow filter directly in parallel with the original one.

/Ubbe

 

[nd5y]

Unless the radio was designed with sockets for user replaceable filters of different bandwidths supplied by the manufacturer then soldering skills are the least of your problems.

If you buy some random filter(s) online just because you think narrower is better then you need to know if the insertion loss and impedance are the same as the OEM filter and whether or not you need to change other components to compensate or completely align the receiver.

 

[cbehr91]

The Icom IC-V86 is one of the few amateur rigs that has separate receive filters for wide vs. narrow.

 

[Ubbe]

Both the IC-v8000 (US version) and FT-8800 use the same type of ceramic filters and use two different switchable filters between FM and NFM. Icom use the CFWS450 type and Yeasu the CFWM450 type. The last letter of F-G-H tell the bandwidth.

I forgot to mention that soldering in parallel cannot be done to either the input or the output pin, or the new filter will have no effect if both the input and output are soldered in parallel. But best are to cut the trace at both ends.

/Ubbe