Yaesu VR5000

[llonen]

So I have one of these come in for repair, deaf across all bands I have the service manual for this and will get to that in due course. The radio has had a hard life before coming into possession of current owner / client. I need to locate a pair of rotary encoders (volume main and sub) part number J62800138 its a commonly used encoder across a range of vertex radios.

There may not be any point in proceeding with the repair unless I can source a pair of these and currently for a part that must have cost pennies the only sources I seem to able to find are in China or the US and are costing upwards of $30 - $40 per unit. See below

[R_J]

Re: Yaesu VR5000

If you order 10,000 units you might get them for pennies but for only a single unit, that's not that bad a price for a dual encoder with switch, at least it is still available.

[llonen]

Re: Yaesu VR5000

Yeah I think the customer is going to feel differently about $60 to $80 dollars just for a pair of encoders that is before I even get started on the repairs to the radio itself and the obvious fees involved.

[stj]

Re: Yaesu VR5000

maybe you can drill into the side and blow switch cleaner into it

[llonen]

Re: Yaesu VR5000

The centre shafts have both been broken off

[llonen]

Re: Yaesu VR5000

Well the customer is happy to pay for replacement rotary encoders so now all that remains to do is establish why the radio effectively has no receive across all five frequency ranges. Although the set produces a decent amount of static noise, just no modulated rf signal. So its going to be a common stage to all five bands probably around the front end, one of the obvious commonalities looks to be the PLL.

[R_J]

Re: Yaesu VR5000

If you need to adjust the center control but can't because the shaft is broken, you can use a fine hacksaw blade and cut a shallow slot in the shaft, then you can use a small flat blade screwdriver to adjust the encoder. Then once the radio is repaired you can replace the encoders

[llonen]

Re: Yaesu VR5000

I have good volume with more than enough white noise coming through so don't need to do anything with the centre control as of yet. Everything more or less works on the set other than one rather important and missing feature, that being a significant lack of all modulated of signals.

From the way the block diagram is layed up the set's front end is divided into 5 more or less sep frequency paths.

0.1 - 30Mhz

30 - 622Mhz

622 - 1240Mhz

1240 - 1860Mhz

and

1860 - 2600 Mhz

The receiver is equally insensitive across all of these frequency ranges, well the samples I have checked at any rate, there does not seem to be much listed regarding failure modes with these scanners and or common problems so I might have to actually put some work into this set lol.

[llonen]

Re: Yaesu VR5000

Actually on that point, the service manual I have for the VR-5000 is somewhat less complete that I would have liked for. Specifically in that it contains only the circuit diagrams, block diagrams and board layouts. If anyone has a more complete service manual I would be greatly appreciative of please.

Kind regards Mark