Originally Posted by skylor
The "OBS" button on the 430W is not for tuning the OBS on the NAV radio and it is disabled in VLOC mode. The 430W OBS button is used for selecting a bearing to a GPS way point.
There is a CDI display available on one of the 430 pages but it's really redundant to the CDI available on the GRT.
The above is correct. Just about the only real use of the OBS button on the 430 is to keep the gps from advancing to the next waypoint, when in a hold.
Your method of setting the OBS on the SL30 works. However, many (I mean me!) find it more convenient to directly control the OBS setting from the GRT HSI (on my Hx I usually split the page, PFD/HSI). To do it this way, you need two way RS232 communication hooked up, and the SL30 has to have a different OBS option selected in its setup -I think ‘electronic pfd’ or something, I don’t have it here. Another plus: if you put the standby VOR into monitor mode, it will be displayed on the HSI as an RMI (bearing pointer) needle. Great for cross fixes.