Go Back  RCU Forums > Radios, Batteries, Clubhouse and more > RC Radios, Transmitters, Receivers, Servos, gyros
Reload this Page >

TF & RF crystals Does anybody know the Country of origin for this terminology please????

RC Radios, Transmitters, Receivers, Servos, gyros Discussion all about rc radios, transmitters, receivers, servos, etc.

TF & RF crystals Does anybody know the Country of origin for this terminology please????

Reply

Old 06-22-2007, 09:31 AM
  #1  
nigel1
Member
Thread Starter
 
Join Date: Jun 2007
Location: KetteringNorthamptonshire, UNITED KINGDOM
Posts: 51
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default TF & RF crystals Does anybody know the Country of origin for this terminology please????

Hi,

Does anyone know the country that uses the terminology TF & RF instead of TX & RX here in the UK Please?

i have purchased some crystals for FM 40 Mhz use in the UK they had the orriginal manufacturers name on the pack but do not seem to work in my UK radio, I was wondering if the frequency might be slightly off because they are meant for use in another country?

I have had some problems finding the right crystals for my Hitech Zebra radio and always seem to be fobbed off with something inferior to that of the orriginal specification.
however this time i thought I had it right as the packaging said Hitech.

kind regards. Nigel.
nigel1 is offline  
Reply With Quote
Old 06-22-2007, 03:49 PM
  #2  
Rodney
Senior Member
 
Join Date: Dec 2001
Location: FL
Posts: 7,769
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: TF & RF crystals Does anybody know the Country of origin for this terminology please????

To be safe, try to use crystals from the same vendor as the maker of the transmitters. Different tranmitters use different oscillator design (is it a Colpits, Hartley or ??) and may require a different cut on the crystal. Also, is it using a 3rd or 5th overtone crystal? Just going by the frequency marked on the crystal doesn't tell you all the necessary information.
Rodney is offline  
Reply With Quote
Old 06-22-2007, 04:06 PM
  #3  
A.T.
Senior Member
 
Join Date: Jul 2002
Location: Auckland, NEW ZEALAND
Posts: 2,581
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: TF & RF crystals Does anybody know the Country of origin for this terminology please????


ORIGINAL: nigel1 Hi, Does anyone know the country that uses the terminology TF & RF instead of TX & RX here in the UK Please? i have purchased some crystals for FM 40 Mhz use in the UK they had the original manufacturers name on the pack but do not seem to work in my UK radio, I was wondering if the frequency might be slightly off because they are meant for use in another country? I have had some problems finding the right crystals for my Hitech Zebra radio and always seem to be fobbed off with something inferior to that of the orriginal specification. however this time i thought I had it right as the packaging said Hitec. kind regards. Nigel.
Refer answersfaulty Hitech Zebra 40mhz FM radio
Regards
Alan T.
Alan's Hobby, Model & RC FAQ Web Links
A.T. is offline  
Reply With Quote
Old 06-23-2007, 05:34 AM
  #4  
nigel1
Member
Thread Starter
 
Join Date: Jun 2007
Location: KetteringNorthamptonshire, UNITED KINGDOM
Posts: 51
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: TF & RF crystals Does anybody know the Country of origin for this terminology please????

Alan T.

That doesnt really help much I'm afraid the terminology you use dosent tally with the information I have on my crystals.
nigel1 is offline  
Reply With Quote
Old 06-23-2007, 10:02 AM
  #5  
onewasp
Senior Member
 
Join Date: Dec 2002
Location: USA
Posts: 2,035
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: TF & RF crystals Does anybody know the Country of origin for this terminology please????

I have no idea what language/country would use capital 'F' where we use a small 'x'.

My advice/opinion is that if they can't get the abbreviation 'right' then I don't have much faith in the product-------particularly a crystal.
onewasp is offline  
Reply With Quote
Old 06-23-2007, 04:12 PM
  #6  
A.T.
Senior Member
 
Join Date: Jul 2002
Location: Auckland, NEW ZEALAND
Posts: 2,581
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: TF & RF crystals Does anybody know the Country of origin for this terminology please????

ORIGINAL: onewasp I have no idea what language/country would use capital 'F' where we use a small 'x'. My advice/opinion is that if they can't get the abbreviation 'right' then I don't have much faith in the product-------particularly a crystal.
Bait taken, hook line & sinker - How much faith can we have in products with "USA labels"? Much is OEM (manufactured ex USA) and just enough assembly and boxing done in USA to qualify for the made in USA label. According to other countries with English as a first or second language, spelling and abreviations used in USA are often mispelt or incorrect. Old established USA brands have been bought by offshore owners and whilst the brand appears unchanged, the product is no longer 100% American e.g. Ace R/C, Sig Mfg with 50% offshore ownership and old kits now prebuilt as ARF ex USA. All known Hobbico products are ex Taiwan & China. The country lists on my web page provide many places you can cross check products and note how many are identical except for the labels and price - you pay more for USA brand labels. e.g. Servo Metal Gear sets
FWIW the crystal tab abbreviations "TF" in lieu of "TX FM", "TA" in lieu of "TX AM", "RF" in lieu of "RX FM, "RA" in lieu of "RX AM" is clearer and has been is use for many years by brands other than Futaba. A manufacturer, who cuts and supply xtals to USA military, has confirmed that Hitec xtals are manufactured to higher specifications than Futaba and JR xtals.
Regards
Alan T.
Alan's Hobby, Model & RC FAQ Web Links
A.T. is offline  
Reply With Quote
Old 06-23-2007, 05:30 PM
  #7  
onewasp
Senior Member
 
Join Date: Dec 2002
Location: USA
Posts: 2,035
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: TF & RF crystals Does anybody know the Country of origin for this terminology please????

Interesting information.

Who'd a thunk it?
onewasp is offline  
Reply With Quote
Old 06-24-2007, 07:51 AM
  #8  
nigel1
Member
Thread Starter
 
Join Date: Jun 2007
Location: KetteringNorthamptonshire, UNITED KINGDOM
Posts: 51
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: TF & RF crystals Does anybody know the Country of origin for this terminology please????

So I have purchased a Tx crystal and an RX crystal in the same package marked Hitech crystals but the crystals have on them TF for FM transmitter and RA for AM reciever, if this is so accoerding to your infomation why would the crystals work when there are no other radios being used in the vicinity, if they are both of different frequencies surely they wouldn't work at all...Strange.

regards nigel1
nigel1 is offline  
Reply With Quote
Old 06-24-2007, 07:57 AM
  #9  
nigel1
Member
Thread Starter
 
Join Date: Jun 2007
Location: KetteringNorthamptonshire, UNITED KINGDOM
Posts: 51
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: TF & RF crystals Does anybody know the Country of origin for this terminology please????

So I have purchased a Tx crystal and an RX crystal in the same package marked Hitech crystals but the crystals have on them TF for FM transmitter and RA for AM reciever, if this is so accoerding to your infomation why would the crystals work when there are no other radios being used in the vicinity, if they are both of different frequencies surely they wouldn't work at all...Strange.

regards nigel1
nigel1 is offline  
Reply With Quote
Old 06-24-2007, 09:09 AM
  #10  
Rodney
Senior Member
 
Join Date: Dec 2001
Location: FL
Posts: 7,769
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: TF & RF crystals Does anybody know the Country of origin for this terminology please????

nigal1. Typically a receiver crystal is 455 KC different than the transmitter frequency for single conversion receivers and 11.7 (approx) MHZ different than the transmitter crystal frequency for dual conversion receivers. Transmitter crystals are usually 1/3 or 1/5 of the frequency being transmitted (the transmitter usually multiplies the frequency of the crystal be either 3 or 5). That is why you can not use a receiver crystal as a transmitter crystal. Whether the receiver cystal is above or below the transmitted frequency is what determines whether the reciever is using positive or negative shift.
Rodney is offline  
Reply With Quote
Old 06-24-2007, 10:16 AM
  #11  
nigel1
Member
Thread Starter
 
Join Date: Jun 2007
Location: KetteringNorthamptonshire, UNITED KINGDOM
Posts: 51
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: TF & RF crystals Does anybody know the Country of origin for this terminology please????

Rodney,

Thanks for that but youve completely lost me in the great jungle of electrical knowledge.

regards. nigel1
nigel1 is offline  
Reply With Quote

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


Thread Tools
Search this Thread

Contact Us Archive Advertising Cookie Policy Privacy Statement Terms of Service