40.08 MHz Crystals

[TANAKASAN]

Does anyone have a source for 40.08 MHz crystals? I've tried the usual distributors with no luck and a Google search just turns up some work done at CERN.

Tanakasan

[G3RZP]

For a price, you can get one made. A lot depends if you want overtones or fundamental, what temperature coefficient, what accuracy, what size, what drive level etc. Quartzlab is a name that springs to mind in the UK.

[W5FYI]

From its web site, "ICM custom quartz crystals typically have frequency ranges of 32.768 KHz to 200 MHz. If your application requires higher frequencies, please contact our crystal engineers at 1-800-725-1426."

www.icmfg.com

[N3QE]

Does anyone have a source for 40.08 MHz crystals? I've tried the usual distributors with no luck and a Google search just turns up some work done at CERN.

Interestingly in a different forum (EMRFD) the request for help with a filter design at 40.0848 MHz just came up.

Is this a IF in some common rig?

Most homebrew stuff, folks put the IF where they can get cheap readily available microprocessor crystals. Long long ham tradition of choosing readily available cheap parts for their homebrewing... 50/60+ years ago hams built their rigs around the surplus WWII/"tank radio" crystals.

Tim N3QE

[TANAKASAN]

Easy, HA5RXZ and I are members of a group working on the same project and corresponding via Internet chat and email. Custom crystals are of course available but the price in small quantities is about $50 a piece.

Tanakasan

[N3QE]

Easy, HA5RXZ and I are members of a group working on the same project and corresponding via Internet chat and email. Custom crystals are of course available but the price in small quantities is about $50 a piece.

Yeah, I know, that's why so many hams go to at least a little effort to use the $1 Microprocessor crystals :-).

Hint hint, nudge nudge.

I'm not saying there's never a need for a custom crystal, but to go and design a homebrew rig using a bunch of custom crystals, is a little like the guy who wants to build his house out of precisely machined 1.6123" x 3.9127" custom lumber instead of just using 2x4's.

Entirely possible to use all-custom frequencies, sometimes there's a good reason for the extra expense, but most of the time you just look at the funny crystal frequency you need, then look elsewhere and discover that a slight change to your original design will let you use the $1 crystals.

[KA5IPF]

Easy, HA5RXZ and I are members of a group working on the same project and corresponding via Internet chat and email. Custom crystals are of course available but the price in small quantities is about $50 a piece.

Tanakasan

Have you ever bought crystals from ICM?

[KF6QEX]

In the distant past I've ordered custom crystals from jancrystals.com
The good news is for about six bucks you can order a programmable oscillator like this one:
http://search.digikey.com/us/en/products/SGR-8002DB-PCB/SGR-8002DB-PCB-ND/755227

[KB1WSY]

>>In the distant past I've ordered custom crystals from jancrystals.com.<<

I was in touch with Jan Crystals a couple of months ago and they quoted $35 plus $10 s/h to do a custom crystal, with turnaround time of 4 to 6 weeks. I did not try them out so cannot give any further info. Another supplier is af4k.com, from whom I have purchased several custom and stock crystals successfully in the past two months.

Martin, KB1WSY

[WB6BYU]

The cost certainly depends on how many you need.  I've ordered a number
of custom crystals and there was typically a $50 minimum order, but it only
cost around $15 per crystal (depending on specifications - a third overtone
for an oscillator is cheaper than a fundamental for a filter.)  So a single
crystal would be $50, but a set of 4 would only be $60.  In one case we
got replacement crystals for a couple boat anchors nearly for free by
adding them to an order that otherwise didn't meet the minimum.

I just ran across an invoice from BOMAR crystals - that would be another
source to check, and "California (or Cal) Crystal Labs" is another name that
comes to mind, but I'm not sure if I remember that correctly.