Minelab GP 3500 Parts?

[jawbone]

I have a GP3500 with a broken plastic shaft on the manual tune potentiometer. Does anyone here know where to find a replacement? Also do the tuning knobs have removable caps to access the retaining screws like the GPX series?   Thanks.

[Tony]

You will need to solder a new one. This is what you need. They are a Bourn's Encoder with the three little legs that need to be soldered onto the 3 matching pins from the detector side....it's a bit fiddly but quite doable. This is the best match but all the Bourn encoders have their own spec sheet.

Just Google 3315C-102-016L and it should hit on Mouser or Digikey if you're in the USA.

https://www.bourns.com/products/encoders/contacting-encoders/product/3315

The only problem is the blue plastic shaft doesn't fit the original knob. You can probably fashion a work around for the original knob but I simply rotate the blue shaft by hand. You may have to drill out the original plastic shaft if it has snapped off inside the knob.

Also, there are no retaining grub screws on any of the knobs. PITA really.

Hope this helps

Tony

[jawbone]

Thank you for the help!

[jawbone]

Ordered 3  3315C-102-016Ls from Mouser (I have 2 3500s) just in case. I'll let you know how it goes. Thanks again!

[Tony]

Solder the middle pin first and then the outer ones......I'm unsure how critical the outer pins are if you get them wrong. Just align with the original encoder. Use very small amounts of solder otherwise the pins can short and the small rubber insulation sleeves wont slide over the connection. You might want to replace the insulation sleeves from the detector side....they are very small. Keep them well back when you make the solder connection otherwise they will react to the heat and stick where you don't want them to stick. The pins on the encoder are somewhat flexible if you need to adjust them slightly.

Bit tricky but definitely worth the effort.