Model Boat Mayhem

Technical, Techniques, Hints, and Tips => Radio Equipment => Topic started by: tigertiger on December 19, 2008, 05:31:07 am

Title: Do Xtals have a direction
Post by: tigertiger on December 19, 2008, 05:31:07 am

On my Tx I can plug in the Xtals in either direction.

Does it matter?
I read somewhere once that it does, buy am not sure if this is correct.

Title: Re: Do Xtals have a direction
Post by: Martin (Admin) on December 19, 2008, 06:16:09 am

I believe they are a "passive" component so no.
I've never seen a crystal with any markings on the legs....
If it works better one way than the other, I would suggest you have a dodgy crystal.

http://www.kvg-gmbh.de/index.php?id=72&L=3
http://www.ieee-uffc.org/freqcontrol/quartz/vig/vigequiv.htm

Title: Re: Do Xtals have a direction
Post by: andyn on December 19, 2008, 02:18:11 pm

No  %)

Shortest answer I could manage...

Title: Re: Do Xtals have a direction
Post by: Stavros on December 19, 2008, 08:06:41 pm

Do you mean 180m degrees around or do you mean TX in Rx and vise versa if the latter sometimes it will work but it creates its own frequency!!!!!!!!!!!


Stavros

Title: Re: Do Xtals have a direction
Post by: tigertiger on December 20, 2008, 12:43:10 am

Hi Dave

I meant 180 degrees.

I believe that Tx to Rx is a big No! No!

Say Merry Xmas to the gang for me.
And a big Hello to Margret

Title: Re: Do Xtals have a direction
Post by: BobF on December 20, 2008, 05:27:26 pm

Although probably technically illeagle as no frequency flag colour, in the old days (late sixties early seventies) we often used them the other way round.
It helped to stop interference problems between receivers, when two people were sailing.

Title: Re: Do Xtals have a direction
Post by: Stavros on December 20, 2008, 06:23:24 pm

Quote from: tigertiger on December 20, 2008, 12:43:10 am

Hi Dave

I meant 180 degrees.

I believe that Tx to Rx is a big No! No!

Say Merry Xmas to the gang for me.
And a big Hello to Margret

Will do I dont think it matters which way around they go in the tx or rx



Stavros

Title: Re: Do Xtals have a direction
Post by: tomocj on January 26, 2009, 05:02:25 pm

no you can use them either way round, as long as tx is a tx crystal and rx is a rx crystal.
chris

Title: Re: Do Xtals have a direction
Post by: Seaspray on January 26, 2009, 05:58:08 pm

they just give the frequency to the circuit  either way does. But don't use a Tx (transmitter) crystal on an Rx (reciever) or visa versa.


Seaspray

Title: Re: Do Xtals have a direction
Post by: Ghost in the shell on January 26, 2009, 06:15:24 pm

tiggsy, happy chinese new year.

in relation to your query, as long as the tx xtal is in the tx, and the rx xtal is in the rx, it doesnt really matter.

Title: Re: Do Xtals have a direction
Post by: tomocj on February 07, 2009, 04:14:34 pm

I agree with Andyn 'NO' any way round will do.Chris