[chirp_users] Offset UV-5R

Tom Hayward esarfl at gmail.com
Tue Oct 29 09:14:55 PDT 2013

On Tue, Oct 29, 2013 at 5:30 AM, Milton Hywatt <mhywattt at yahoo.com> wrote:
> Why do I need a frequency in the offset cell even for a
> simplex channel?

This is a question for your radio manufacturer, but I'll entertain it anyway...

> I was redoing my channel list yesterday
> and noticed the radio would not transmit on a channel that
> was for simplex crossband use into my base radio. I had removed
> the frequency figuring that if it is simplex it doesn't need an offset
> entered since it is the same as the RX/TX entries. Well that's not
> the case. It's no biggie. But I would like to understand the logic
> of needed the simplex frequency entered into the offset cell. Or
> maybe I'm doing something else wrong?

The UV-5R uses 0 in the offset column to activate the TX inhibit
feature. It's a clever way to save storage space in the radio. The two
features are mutually exclusive: When you want TX inhibit, you don't
need to store a TX frequency, so they used a 0 value in that column to
activate the TX inhibit feature.

The Japanese ham radio manufacturers use two columns for TX frequency,
duplex and offset. This is what Chirp's interface is modeled after.
With these radios, you can put anything you want in the offset column
when Duplex is set to None, because they don't overload usage of that
column--offset is completely ignored in simplex mode.

To make things easier on everyone, Chirp has a feature to hide unused
data columns. Select View -> Hide Unused Fields. Now the Offset field
will be hidden (blank) in simplex mode, and you won't be tempted to
fill it with zeros.


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