Hi, Steve and All;
>Really hve to make ure that an opto device has enough gain (current transfer
>ratio)
I have made sure that an opto device does not have enough gain, compared with
a transistor interface.
>> interface I tried lpt keying when I run writelog, but not succeeded.
>
>Does not succeed mean that some elements are short - as yu said before.
No, I mean that the interface cannot drive the keying circuit of my rigs.
>> Then I found that the output level from my Keying interface is not enough
>
>Why not post what your rigs are so that people with same rig may help.
>Also describe your interface circuit.
I use an IC751A and an FT847. My interface is the folloiwng.
lpt 17pin --vvv-----+ +------- Key
SLCT 100 ohm | /C
--- |/
\ / |\
--- | \E
| +------- GND
lpt 18pin ----------+
GND
I use a Toshiba TLP521. I always compare this interface with that described
on CT manual.
>Level is higher ? Where in circuit ?
I mean the output level of my interfaces.
>OH! Do you have a printer installed on the LPT port ?
No, because I use a printer installed on another PC via home LAN.
I will try it.
----
Katsuyuki Ishii kkii@hcc1.bai.ne.jp
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