Changing a quartz crystal's frequency with sandpaper and a pencil

[@johnwest7993]

The reason the old crystals were mounted in Xtal holders was specifically so you COULD grind them thinner to go up in frequency, or use a pencil to add to their mass and send them lower.

[@johnwest7993]

I got moved from a job as a production test tech to a job in the R&D lab (with a good raise) when I figured out that an intermittent lock-up problem on a microprocessor board in our product was due to a xtal manufacturer's production flunky leaving out the insulating sleeves that was used to insulate the crystal circuit from the metal shell, a shell that our circuit tied to Earth.

[@ericdee6802]

I remember watching my Dad recalibrate his Ham radio that used those huge bakelite crystals, he also had a large selection of tuning forks used in the process.

[@UndernetSystems]

This is crazy! I love how the lead pencil technique made it sound like crystal was being tortured!!

[@cosmo1494]

it was - against the Geneva convention, which was so named thanks to the original Swiss watchmakers

[@Falkon303]

This is the best video I have seen all year. I also loved your pencil DJ scratching.

[@wadepatton2433]

Drivin' my dogs mad. But I like the idea and have more of my own. Thanks for showing your chops!

[@markonis100]

Absolutely my new favorite video of yours. That wailing, tho

[@jimmiller9330]

You may not need to cut the case. In my crystal, the cover was just soldered on and was easily removed with heat from a solder iron.

[@tedlinaf3536]

we adjusted freq. in factory by starting higher and vacuum depositing more silver on the electrodes to bring them down

[@darrenglasson7200]

I have ground the bottom lip of the xtal to remove the case then I have soldered it after lowering the freq with a perminate marker(max 20khz) have to wait for marker to dry before stable.I used this method on a codan to adjust the freq I think I even done this with a 2 mhz xtal using the codan this put it on 3650 cheap 80 meter rig.Great to see people out there still experimenting. 73s

[@kaptenalgysson8540]

Hello VK3YE, have you try to lower x-tals with pencils for printed circuit boards? G0UPL have desribe a method of higher lowering of frequency with penning of crystals, and better to use a Dremel tool to open up HC-25 xtals then a nibbel... Good luck from SM6AAL in Sweden

[@2GFactFinder]

Maaaaannnn....How you got this idea......?????.......Driving me crazy.......!!!!!!

[@ovalwingnut]

Excellent 👍😁 "The Element Whisiper"

[@elkabong6429]

The penciling technique reminded me of a theremin device!

[@ingussilins6330]

Buy a quartz obelisk from the esoteric shop. Stick foils on both sides. Connect to the transistor circuit.

[@southsidehopper3662]

Hey Peter, Thanks for all the great tutorials on RF. You are a great help when it comes to understanding the how these circuits operate. After seeing this video, I realised using the pencil added conductivity to the existing plate. It started me thinking what would happen if you added gold leaf to the plate. Obviously, bonding may be a problem. One possible way to adjust the frequency would be to add heat paste to the plate and I was wondering if you have ever tested this theory. Best regards, Sutho….

[@GaryLordsWayMinistry]

You want to reduce the frequency use a higher ohms resistor as well, like a carbon based resistor that is not wound of the inductance in the circuit will change the oscillating of the frequency as well as n any tuned LCR circuit does,

[@MauriatOttolink]

Peter. Where the case is soldered, it CAN be opened with careful and swift desoldering. It survived the soldering at manufacture. Your demo Xtal is soldered. If there is little hole on the corner of the case at the far end & if it's opened during desoldering, be sure to re-solder it before reassembly. The hack saw is the only hope with cold-welded holders. Some were filled with inert gas. May not be today. You lose any gas of course by opening the holder Plates were usually gold plated when I was in the xtal business but yours don't look like gold. Gold can be thinned by exposing it, VERY briefly to the brown fumes of Aqua Regia... FUMES! BRIEFLY! and then promptly washing in water. It's still changing slightly on its way to the water!!! This takes it HF. Dry it in low heat or Isopropanol. Aqua Regia is dodgy stuff. No idea where you might get it...(Nitric Acid and Hydrochloric acid.) LF was achieved by sputtering more gold onto the plates but that's a manufacturing process requiring elaborate apparatus. Soft pencil works for LF but it's not stable and CAN drift HF again over time. Variable L or C in series with the rock is far more convenient but doesn't give much shift. Nibbling the quartz is a good way to break it in two pieces. That will send it VERY LF. 00.00Mhz Grinding is a bit difficult because quarz is extremely hard. Make sure all the grinding paste is cleared when you reach your QRG. To be honest, you set yourself a tough goal starting at 6.4 Mhz., IF 40 metres was your target. The manufacturers would have got a lot nearer by lapping the xtal blanks before plating and final adjustment Did you know that German WW2 Radios had NO xtals? They had no source of quartz, Silicon Dioxide. Everything was L/C.

[@vk3ye]

Thanks. My attempt at desoldering was unsuccessful. Maybe it requires a higher temperature?

[@MauriatOttolink]

VK3YE. No so much higher temperature but more heat to melt it pronto before the heat travels.

[@kp4md]

Ditto. The frequency of such a plated quartz crystal can also be raised by incrementally rubbing off some of the plating with a rubber pencil eraser.

[@kp4md]

I prefer desoldering the case for frequency tweaking, as replacing the cover will restore the crystal's relative insulation from ambiental temperature changes. Take into account that the presence or absence of the cover also shifts the frequency.

[@ppcasm_1278]

You could probably use a fiberglass scratch pen like you use for grinding away PCB masking

[@lloydcarpenter2044]

What about Raising a crystal frequency with super conductor.

[@billdumke211]

I once built a SSB crystal filter using FT-243 Crystals by using Ajax (raises freq.) and Pencil Lead (lowers freq.) to tune each crystal. It works.

[@kp4md]

Yes, grind non-plated quartz crystals with a fine abrasive such as toothpaste against flat plate glass. Irregular grinding with a coarser abrasive will decrease crystal activity.

[@aaronwong2773]

great job

[@phillipsmiley5930]

I was doing his with FT243 crystals which have a screw on case over 40 years ago

[@cejaybee]

I'll have to try Conductive/Silver Ink...

[@guillermosempron5776]

Please post the link to the video that you talk about. I cant found it in KZbin.

[@vk3ye]

kzbin.info/www/bejne/oGimhGd3bdx1Z6c

[@JUANKERR2000]

Has anyone tried this technique with ceramic resonators, say 455 kHz to 465 kHz or 470 kHz to 465 kHz?

[@BykaZoid]

if you attach the needle and microphone will be FM ????

[@alicomando1195]

Hi How can I Make 24 Hours And 45 Minutes Clocks Measurement Let's Say For Other Planets well Actually My Circadian Rhythm Is 24 Hours and about 48 Minutes on Average I have Delayed Sleep Phase Disorder Dspd Non-24 Hours some People Call Me Martians I Know It Is Frustrating To Wake Up 45 Minutes Later Every Day But I accepted This As a 32-year-Old i am interested To Make Clock That Tracks My Body clock Do You Know Any Html Or JavaScript Or Any Other Codes To make or Is there any Html Codes Of Martian Time That I Can change It From 39 Minutes To 45-48 Minutes Longer? If Not How Can I Slow Down A Quartz Clock To Run little Slower 3% Percent Slower Thank You So Much Sir I hope You Have Some Solutions For Me

[@vk3ye]

Can't help, sorry!

[@ondrejjanovec6700]

Good video.

[@Derrick6162]

Dotting the crystal with a permanent marker yields better results...Thanks

[@markhonea2461]

You could tune it very precisely with the pencil, given enough attempts. A spy frequency perhaps?

[@Dime_Bar]

I can never get anywhere near a 100 strokes never mind another 50 strokes before it's all over.

[@la7dfa]

By watching these videos I do not even have to stroke. It is pretty cynically targeted at nerds.

[@xHizukax]

So pacman is a crystal creature. Now I know!

[@Neo_Chen]

When penciling the crystal, I thought I hear it screaming.

[@muctop17]

To get an impression, what a crystal is look: kzbin.info/www/bejne/rXnIn5ypiLmIh7s and how many work is needed to make some.

[@MHEletronic]

Great. Try dotting with Edding 3000 or similar. It works. 73, DF2OK

[@markhodgson2348]

I use these in my ghost box

[@orpheuscreativeco9236]

Sounds like Rage Against the Machine 🤘😂