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Old 07-10-2007, 06:27 PM
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maktec
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Default pos and neg shift???

Any one help me with the difference between a receiver with positive or negitive shift,, how can I tell the difference?
Thanks
George
Old 07-10-2007, 06:38 PM
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bruce88123
 
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Default RE: pos and neg shift???

An FM (or PCM) RX operates on a basic carier frequency. The frequency is then "shifted" from that frequency to encode the signal information. It doesn't say anywhere on the RX shich way it shifts. Some shift pos and some neg and some will go either way, either automatically or via jumper programming. A given manufacturer is usually consistant in having ALL of his products shift in the same direction or both.
Old 07-10-2007, 06:40 PM
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Default RE: pos and neg shift???

It's actually the TX freq that shifts and the RX has to be able to track it. Little detail.
Old 07-10-2007, 06:49 PM
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Bad_Daddy
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Default RE: pos and neg shift???

maktec - Airtronics and JR radios use positive shift. Futaba and Hitec radios use negative shift.
So, which one you need depends solely on what brand of FM Transmitter you are using.
Old 07-10-2007, 08:36 PM
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Default RE: pos and neg shift???

...Hitec also makes some [link=http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXCXM9&P=7]positive shift[/link] receivers that work with JR & Airtronics, and [link=http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXN524&P=7]selectable shift[/link] and [link=http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXKYK3&P=7]auto-shift[/link] receivers that work with both.
Old 07-10-2007, 09:44 PM
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JohnBuckner
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Default RE: pos and neg shift???

Exactly what make and model Tx are you trying to match up a rx to? All posters have given good info but some manufacturers now produce some models that are shift selectable and some have had this feature for more than ten years now, so what do you have?
Old 07-15-2007, 10:06 AM
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zenith16
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Default RE: pos and neg shift???

Johnbuckner< I've got a negative shift JRRS6UL micro receiver. Is there anything I can do to make it a Positive shift and use it with my JR radio???Thanks
Old 07-15-2007, 11:45 AM
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Default RE: pos and neg shift???

I can find no referance to that rx model number. Seems odd since in the past JR has provided only positive shift Tx and Rx's. Possibly this is something new can you provide a direct link to this Rx.
Old 07-15-2007, 03:48 PM
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bruce88123
 
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Default RE: pos and neg shift???

I found a JR ad where this had been available as EITHER positive OR negative shift depending upon what you ordered. They did not mention being able to convert it and I doubt that you can or they would have mentioned such a beneficial feature.
Suggestion: Ask in the JR support forum and get a reply from JR directly or contact JR product support at [email protected]
Old 07-15-2007, 04:32 PM
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Default RE: pos and neg shift???

Thank you for finding that Bruce.


John

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