All,
The LEDs are 1x5mm rectangular. NTE3160 (red) and NTE3161 (green) are commonly available and I see a few eBay sellers with other branded LEDs in the same form factor. Pretty sure Rohm and Liteon made these at some point.
Yaesu used the same type LEDs for the FT-707's S meter, in a green-yellow-red arrangement. These can be cannibalized if all else fails...as can the numerous models of CB radio and car audio equipment which also employed them.
When swapping the LEDs, remove the Attenuator shaft from its coupler (and from the radio). Unscrew the top-most two screws which retain the front panel and tip it downwards onto your bench. I put bubble wrap under the radio and on the bench as a cushion. Work on the Display Board LEDs first - all three boards come out sequentially. A good temperature-controlled vacuum solder sucker (Pace, Metcal, Weller, what have you) is essential for the removal of these LEDs. The holes in the board are somewhat of a tight fit for the leads even without solder. It may take a few sessions with the desoldering tool at each LED for remove them, working each out bit by bit until free. Afterwards I apply some solder to the now-vacant holes and use the desoldering iron to completely clean them.
Insert the new LEDs, carefully replace the front-most Display Board as you guide all the LEDs into their respective front-panel holes. You want to ensure the board is seated correctly before positioning the "loose" LEDs you changed out. When all looks good, solder and cut the leads flush then reinstall the middle and rear Display boards. The Keypad Board LEDs are MUCH less fiddly in terms of removal and installation. Trickiest thing here is to make sure the keys and foam inserts stay in the front panel when you lift the Keypad Board and that all the keys work properly when it's re-installed. There are three wires which must be desoldered from the board as the LEDs are being removed: Yellow (RXC LED), Green (TXC LED) and purple (Ham VFO LED). It goes without saying that if you elect to change other LEDs these instructions are partially accurate...but this should give one a good idea about what to expect. I also remove the Memory Switch and FWD Set potentiometer from the front panel prior to removal of the Keypad Board.
The same caveats hold true for positioning the Keypad Board LEDs as the Display Board's parts: Ensure correct position of ALL LEDs (including the OEM ones) before you solder; the freshly installed parts can be moved in or out as needed prior to application of the iron. Re-solder the three wires you removed then attach the insulator/hold-down plate which covers the RX/TX Clarifier LED area of the board. Remember the solder lug which grounds a small capacitor from the Memory switch. Replace the Memory Switch and FWD Set pot along with their knobs.
In my new color scheme, Green is Good. The Ham VFO and VFO Control indicators are both green, so at a glance if this is what you see you're good to operate without worries. I changed the RX and TX Clarifier LEDs to red, as well as the Split and Remote (CAT) LEDs. The Gen VFO was left yellow as were the others. If the operator sees red in the status window and yellow in the VFO indicator area, it behooves him or her to pay attention to which VFO is selected for TX and which other operating parameters are in play so as not to damage the rig.
I'll touch briefly on the "Gen TX Mod" (Yaesu kit) in a separate posting.
73 - Fred, N8YX
Mat Breton N8TW
N4PL