Digest Number 57
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Posts: 46,084
>
>
> I purchased the TX-66 transmitter, which is the more expensive unit with a SAW
> resonator, hoping for better stability than the standard LC module. The
> receiver is the RX-66 super-regen. Performance and workmanship was very poor.
> Even at 10' range, the received signal dropped out as surrounding objects
moved
> around. The low logic level from the receiver was ~1 volt, the high level was
> OK. I used the recommended 9" antenna on both units, and tuning the receiver
> as recommended did no good. I tried to phone Ming several times, but there
was
> no answer. If I recall correctly, they didn't reply to email either.
Check the single loop coil on the RX. If it gets bent over from near vertical
the range is greatly reduced. I got them on the phone years ago trying to
figure the maximum baud rate as the data sheet only says it depends on
bandwidth, which they don't give. I was told the bandwidth is 10kHz.
>
> I purchased the TX-66 transmitter, which is the more expensive unit with a SAW
> resonator, hoping for better stability than the standard LC module. The
> receiver is the RX-66 super-regen. Performance and workmanship was very poor.
> Even at 10' range, the received signal dropped out as surrounding objects
moved
> around. The low logic level from the receiver was ~1 volt, the high level was
> OK. I used the recommended 9" antenna on both units, and tuning the receiver
> as recommended did no good. I tried to phone Ming several times, but there
was
> no answer. If I recall correctly, they didn't reply to email either.
Check the single loop coil on the RX. If it gets bent over from near vertical
the range is greatly reduced. I got them on the phone years ago trying to
figure the maximum baud rate as the data sheet only says it depends on
bandwidth, which they don't give. I was told the bandwidth is 10kHz.