I have a buddy who set up a public node which uses an Alinco (yea, I know…) as a simplex radio. He’s using a Repeater Builder RIM Lite as the HW interface and all works OK except it uses discriminator audio. If he enables de-emphasis in simpleusb.conf, the audio sounds fine but DTMF decode stops working… Playing with levels doesn’t seem to improve the situation so I’m thinking perhaps twist is the issue. With de-emphasis off, audio is horrid (tinny, blah blah) but DTMF does decode.
Has he tried usbradiotune ?
See instructions in the wiki.
You must get the receiver audio correct. Then adjust the tx to your liking if any needed or a want to tweek.
For the system sound is finite without adjustment.
It’s the only way to achieve audio balance for links, system and receiver…
While it may sound good at the tx, obviously, it sounds bad at the system or you would have dtmf.
Just trying to put you in the right mindset for approaching this.
The RIM Lite uses simpleusb and apparently there is no valid command ‘radio tune rxvoice’ available when that driver is used
Have you tried radio tune simple USB?
I’ll have to ask my buddy but I think he said he did run that
The RIM Lite can support both usbradio and simpleusb channel drivers. If the audio “sounds fine” when de-emphasis is enabled, then something is wrong with the radio transmitting the tones, the Alinco’s frequency response, or the nodes audio levels haven’t been set up properly. If it’s an Alinco DR135, 235, or 435, they have good audio, and are pretty flat. Whether your friends node is using simpleusb or usbradio is inconsequential. Decoding DTMF isn’t ever a problem when the application is set up properly - no matter what channel driver is used - unless there are issues elsewhere. I know of several installations where an Alinco is used to remotely connect ASL to a repeater because Internet is not available locally at the repeater site. Remote controlling of the node can be done by unmuting the DTMF through the repeater. The remote node reliably decodes the DTMF tones, which is more to ask than decoding directly on the node itself because of the involvement of yet another RX and TX. Make sure the owner doesn’t have the radio programmed for “narrow” which can severely distort the audio from a wide-band transmitter.
Thanks Kevin - first time I’ve ever heard the RIM Lite could use either driver. Good to know (I think).I use 4 of 'em with my various nodes but have the (amazingly enough) RC210 versions 
and they all work great.
His Alinco audio sounds typically tinny with de-emph turned off so it’s obvious the RIM is being fed disc. audio. As I said, enabling de-emph in the conf file settles the audio down and it sounds just fine. I’m pretty sure he knows enough about narrowbanded radios for this not to be the issue but I’ll remind him to check it anyway. All can say for sure is I can monitor the asterisk CLI and see DTMF isn’t being recognized with de-emph enabled but is recognized when it isn’t.
The radio is a DR-435 but I don’t which version of the RIM he ordered - the 9600 or the other but I’m pretty sure he hasn’t mod’d it. I’ll relay your info to him and let him check out a few things
There is no twist adjustment. But there are common problems decoding TTs:
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P/L (CTCSS) is not filtered. Be sure the PL filter is on in whichever channel driver you are using.
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The deemphasis setting is wrong. Toggle it on or off in whichever channel driver you are using.
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Be sure to set the RX audio level so voice peaks are near the 5khz level.
The final result to this saga.
We changed his driver over to usbradio.conf and DTMF is good as well as RX audio is now properly de-emphasized. Go figure…
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