[chirp_devel] [PATCH] [TK-270] Allow programming Kenwood commercial UHF radios in the 70cm band. #4709

[Pavel Milanes Costa]

Hi, sorry for the delay, the wait is justified.

Attached to this email I send to you a short survey about the OEM vs 
Real limits of some of the Commercial Kenwoods radios. (VHF and UHF).

In past days I asked some of my ham fellow to pass by my home and borrow 
his radios for a few minutes; the test was to put a 0.5 Mhz jumps in the 
channels of the radios and check where they fail to look the PLL VCOs, 
sure I tested them on either mode (RX o TX) data shows that RX will go 
about -6% in the lower edge and is the first to fail in the upper edge 
with a mean of a +4.0% (in one case TX can work up to 8%!)

In short:  either VHF or UHF models can tolerate safely a -4% and + 4% 
as a rule of thumb (working on both RX & TX), data from my experiments 
shows that in most cases this is safe.

As -4.0% is the minimum that will allow to work the ham bands either on 
VHF as in UHF I will set a +/- 4% on both edges.

So, I'm submitting patched to the 3 drivers that support the tested 
Commercial Kenwood radios, I will create a new issue explaining the 
situation and data found and will send the 3 independent patches against 
this issue, I will link the Tom's issue as a subset of this.

This will allow to use that radios in Ham bands and yet the OEM 
ident/model string in the settings area will show the real OEM values, 
just as Tom suggested.

73 de Pavel CO7WT.