Nice replacement knob for FDM-DUO #fdm-duo


Jim AJ8S
 

I have had trouble with the tuning knob on my Elad FDM-DUO ever since I got it. The machining of the threaded hole for the set screw was poorly made. You cannot order a new one from Elad because they are always out of stock. Finally I found a very good replacement from LoveMySwitches.com. The set screws engage the shaft very well even though the knob info says it is designed for use with a "smooth" shaft. The O.D. is very slightly less than the Elad knob. Of course the encoder is still a bit wobbly and the new knob has no effect on that.

Silver Anodized Aluminum Knob - "Full Moon" - 1/4" Smooth Shaft (41mm OD) $7.99

https://lovemyswitches.com/silver-anodized-aluminum-knob-full-moon-1-4-smooth-shaft-41mm-od/



Paul Andrews
 

Nice find!

73 - Paul - W2HRO

On Fri, Sep 17, 2021, 11:08 Jim AJ8S <aj8s@...> wrote:

I have had trouble with the tuning knob on my Elad FDM-DUO ever since I got it. The machining of the threaded hole for the set screw was poorly made. You cannot order a new one from Elad because they are always out of stock. Finally I found a very good replacement from LoveMySwitches.com. The set screws engage the shaft very well even though the knob info says it is designed for use with a "smooth" shaft. The O.D. is very slightly less than the Elad knob. Of course the encoder is still a bit wobbly and the new knob has no effect on that.

Silver Anodized Aluminum Knob - "Full Moon" - 1/4" Smooth Shaft (41mm OD) $7.99

https://lovemyswitches.com/silver-anodized-aluminum-knob-full-moon-1-4-smooth-shaft-41mm-od/



G8NRY
 
Edited

Nice. My only concern would be that the new all metal knob is much heavier than the original so will put even more stress on the already very weak encoder shaft leading to even more wobble and failure. Maybe look at adding some bracing e.g. felt washer?


John Fell
 

Yes ,the new version knob looks nice and screw retention is improved from what you say .

The original knob has a recessed rear which allows you to add some low density foam (6mm thick is optimum) .This in conjunction with the locking screw allows you to set the knob so that it can be turned easily but adds a slight drag force , which prevents inadvertent frequency changes from slight finger contact when working very narrow bandwidths .The foam density allows the knob to be depressed when required and removes all traces of shaft wobble .

All you need is a 1/16"/1.55mm A/F Allen Key and a sharp craft knife to cut out the annular foam insert and  if you don't like the mod , it comes off the same way .

73
John
G0API


On Sun, 19 Sept 2021 at 13:38, G8NRY <info@...> wrote:

[Edited Message Follows]

Nice. My only concern would be that the new all metal knob is much heavier than the original so will put even more stress on the already very weak encoder shaft leading to even more wobble and failure. Maybe look at adding some bracing e.g. felt washer?


Mike
 

Thank you for posting this replacement, I just ordered one. 


Paul Andrews
 

My LoveMySwitches.com knob arrived today.   See attached photo.

The new knob is exactly the correct size.   It has two (2) set screws and is very stable on the encoder shaft.

The knob also has a very nice cavity for placing a piece of felt.  This was suggested on this list.

The felt provides very comfortable drag.  It's smooth, quiet and the encoder shaft has additional support.

The factory tuning knob is fine.  If a second set screw could be added and a place for the felt - it would be perfect.

73 - Paul - W2HRO



On Fri, Sep 17, 2021 at 12:08 PM Jim AJ8S <aj8s@...> wrote:

I have had trouble with the tuning knob on my Elad FDM-DUO ever since I got it. The machining of the threaded hole for the set screw was poorly made. You cannot order a new one from Elad because they are always out of stock. Finally I found a very good replacement from LoveMySwitches.com. The set screws engage the shaft very well even though the knob info says it is designed for use with a "smooth" shaft. The O.D. is very slightly less than the Elad knob. Of course the encoder is still a bit wobbly and the new knob has no effect on that.

Silver Anodized Aluminum Knob - "Full Moon" - 1/4" Smooth Shaft (41mm OD) $7.99

https://lovemyswitches.com/silver-anodized-aluminum-knob-full-moon-1-4-smooth-shaft-41mm-od/




--
Paul Andrews
SVP - Sales & Marketing
TelVue Corporation
1-800-885-8886 x102