I am steadily working my way through the learning curve and can occasionally land on or near the runway and sometimes the right way up - however.
737 NG.  
I am trying to understand tuning the localiser, glide slope and beacons.
I am flying short hops between EGGD and EGFF generally at half light and it is possible to see each airport from the other following take-off.
When I set the nav radios, I understand the ILS frequency but how do I set the localiser frequency? I have discovered there is not a set relationship between the two frequencies. The glide slope frequency offered in the FMC works effectively and the localiser also (not that I can land using them solely!).
Then there are the beacons. Where do or can I set the VOR frequencies?

30 minutes ago, GBW said:

I am steadily working my way through the learning curve and can occasionally land on or near the runway and sometimes the right way up - however.
737 NG.  
I am trying to understand tuning the localiser, glide slope and beacons.
I am flying short hops between EGGD and EGFF generally at half light and it is possible to see each airport from the other following take-off.
When I set the nav radios, I understand the ILS frequency but how do I set the localiser frequency? I have discovered there is not a set relationship between the two frequencies. The glide slope frequency offered in the FMC works effectively and the localiser also (not that I can land using them solely!).
Then there are the beacons. Where do or can I set the VOR frequencies?

ILS has one frequency, but not all approaches use lnav and Vnav.  Localizer is when you use the frequency to track laterally but fly your own GS, the other uses it for Vertical guidance and you track it laterally, ILS does both it is one frequency. As for VOR  they are far becoming redundant so if XPLANe updates its database you may find some missing. On the hold 737 you had to tune both NAV radios to the ILS to track the glide slope. Why dont you just look it up, there are a gazillion explanations out there.

I did my best before posting but just received lists of GS and LOC frequencies.  E.g. Bristol (EGGD) ILS is listed as 110.15 without stating which transmitter it refers to.

Following your "gazillion" recommendation , I found this (WIKI);-

 

"Two signals are transmitted on one of 40 ILS channels. One is modulated at 90 Hz, the other at 150 Hz. These are transmitted from co-located antennas. Each antenna transmits a narrow beam.

Localizer (LOC) and glide slope (G/S) carrier frequencies are paired so that the navigation radio automatically tunes the G/S frequency which corresponds to the selected LOC frequency. The LOC signal is in the 110 MHz range while the G/S signal is in the 330 MHz range.^[2]
LOC carrier frequencies range between 108.10 MHz and 111.95 MHz (with the 100 kHz first decimal digit always odd, so 108.10, 108.15, 108.30, etc., are LOC frequencies and are not used for any other purpose)."

Wiki claims there are two frequencies which is what I discovered.  But the reference to "automatically" I think solves my problem.

I use both GS and LOC indications on the displays to guide me in (but still miss!).

Now - what about VOR?

(Incidentally, I have no shame in admitting my lack of knowledge and aircraft systems are complicated.  Comments suggesting a lack of effort by the enquirer tend to put off newby requests).

VOR frequencies are set in the Nav radios on the pedestal of the 737. Typically for a turn toward a localiser, you note the location of the runway nav aid and the magnetic heading of the runway you wish to land on. You draw a line on the reciprocal heading from the runway out to about 10-20 miles, then you come at that point on something like a 40-30 degree offset angle with the heading of the runway put into the CRS windows on the MCP and the nav aid frequency tuned into both nav radios. Initially use the HDG control on the MCP with the autopilot, but select LOC on the MCP. when you fly into the localiser radio beam, the autopilot should detect this and turn to align the runway.

If there is a glideslope signal you can then select APP on the autopilot, and select two autopilot buttons CMDs to fly an automatic descent, if not, you'll have to fly an approach descent manually, which you can either do visually using the PAPI lights at the side of the runway as a guide, or purely visually by aiming at the touchdown marker on the runway (a big white mark just after the piano keys), if you keep two red and two white lights visible on the PAPI as you descend, you will be on a 3 degree descent profile.

If you look up a chart for the runway, it should tell you the various altitudes to be at as you come in for a landing, so you read these off on the PFD when you have the runway beacon tuned in, and use that as a guide for your descent.

Thanks - that is really helpful.

I used to work for Smiths Industries who produced a lot of this kit but I was on the naval side.  (I assume they still do but are part of GE now.). (Still pay my pension though!)

I realise the ILS frequencies are set in the FMC and the results are visible in the display on the pedestal.  I have also noted that the standby frequency can be adjusted there manually.  The ADF frequencies in the FMC duo not seem to appear on the pedestal.  Do they refer to VOR beacons?  I can change the COM frequencies.

I am acquainted with SIDS and STARS although that took a bit of searching.

Thanks again.