Hitec Focus 6 receiver question

Just picked up a 2nd hand Focus 6 FM (tx only) (Australian model-36Mhz). Seller quoted condition as "good but servo's jittered if transmitter left in
sun". As I'm considering using it for indoor, I didn't really care. Added new Antenna, new battery, new 'dual conversion' crystal and tried with old existing dual conversion receiver (same freq dual conversion crystal). No joy. Transmitter shows full power, but no indication receiver is hearing it. Receiver is not faulty as it works perfectly with my Hitec Master 7 radio. Crystals not faulty as also tested with Master 7.
Is my problem in trying to use a dual conversion receiver and/or dual conversion crystals with this radio?
Should I buy a single conversion receiver and matching crystals?
Any help would be greatly appreciated.
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As long as you're matching dual conversion crystal and rx, it should work. Any possibility the rx shift is different from the old to the new? I'm not familiar with the master, but I'm assuming everything else is matched. Is the Master also FM?
Good Luck, PCPhill

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Master 7 is also 36Mhz FM.

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The full power indication is battery power only and has nothing to do with transmitted power. Your best bet is to send it off to a shop specializing in transmitter tuning.
-- Paul McIntosh http://www.rc-bearings.com

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Er, let me restate that.... (serious sleep deprivation.)
Make sure the new transmitter has the shift selected to match the RX. Most Hitecs are have selectable shift and it may not match your RX.
PCPhill
----- Original Message -----
Newsgroups: rec.models.rc.air Sent: Saturday, August 14, 2004 10:36 PM Subject: Re: Hitec Focus 6 receiver question

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Gerrit, I don't understand the bit about fitting a dual conversion xtal to your xmitter. Dual conversion is a term that applies only to recievers - fitting a dual conversion xtal into a xmitter would ensure that transmits on a frequency other than the one expected.
I suggest you try it with an ordinary xtal of the frequency of one of your known-to-be-working rceivers, and see how it goes.
David - who doesn't know much about planes, but a bit about radios
Gerrit Bakhuis wrote:

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If we're not supposed to eat animals, why are they made out of meat?

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The crystals are a new hitec branded set (specifically labelled "Dual Conversion F.M"), with the stickers on the crystals stating "CH624;36.240 RF" and "CH624;36.240 TF", so I assume the RF is dual conversion and the TF is standard?
I made sure I put the RF in the receiver and the TF in the transmitter (duh!).

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Ok, then sounds good. One last thought (well 2 actually) I presume you have checked with Hitec to make sure the receiver IS a double conversion RX?
The other thought is that you really need to find out where the problem is - the Xmittr or the RX.
There must be someone at your club that flys on the same frequency - you can check your RX with their Xmitter, and your Xmitter wiht their RX. At least then you will know which is faulty.
Good luck
David
GeeBee wrote:

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Can confirm receiver works with another Hitec Transmitter (Master 7) (tested with 2 separate sets of crystals - same 2 sets used with this transmitter, so I can only assume that Focus 6 is faulty. Will send off for repair.

RX?
"CH624;36.240
TF
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Gerrit Bakhuis wrote:

It sounds like you're trying to put a dual conversion crystal into the transmitter, which makes no sense - there's no such thing as dual conversion in transimtters. What you need in the transmitter is a Hitec TX crystal that matches whatever RX frequency you're using on the receiver.
Russ.
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Move to Futaba....
Mike Reiman The Reiman Corporation, CEO 2505 South Ocean Boulevard Palm Beach, Florida 33480
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Put the old crystal back in and try it on the original freq and see if it works. If it works with the old set up then the problem is the new crystal which I suspect belongs in the rx. If it is a dual conversion, its oscillating freq will be different from that of the normal tx crystal to allow the dual conversion. As stated, there is no such thing as a dual conversion transmitter crystal. The old Focus doesn't allow a transmitter "shift" as it is not programmable but as all HiTec's use the same shift, it is a non issue. I have an older Focus 6 as well. It works just fine. The servo jitter when exposed to the sun sounds like an overheating problem in the tx.
Hope this helps
Jim W

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