No problems, just thought a clearer version may assist. I don't recall if
Yaesu had a propensity for using IC sockets (I fear not) but you should be
able to pull the segment drive pins down to the reference voltage (pin 1 of
the IC) using, say, a 10k resistor without causing damage. (Is the display
connected via one of those fairly rigid ribbon cable connectors??). Thus you
can light the segments up one by one (for all digits, obviously) to check
operation. OKI made these beasts but don't even list them in the obsolete
components
http://www2.okisemi.com/us/docs/PrdD...oducts.txt1525 but an
e-mail may be rewarded.

www.1sourcecomponents.com claim to have these IC's in stock, but who knows
how much. I think I'm actually looking at one right now on a VFD board from
an ancient satellite dish controller (I'll confirm the part number if it
becomes an issue), but as I'm here in New Zealand it may be of limited use
if you can find one more local to yourself. Let me know though, I can send
it over.

Cheers.

Ken

"Henry Kolesnik" wrote in message
om...
Ken
Thanks for the point. I have a schematic and have read some of the manual
and it is misleading. I
may be clueless but not as clueless as the guy who wrote them manual. I
trust the schemtic because I can follow it on the PCB. The manual is all
wrong on how the display works.

73
Hank WD5JFR

"Ken Taylor" wrote in message
...
Try here for a copy of the manual (looks complete, but I can't vouch for
it).
http://www.crocuta.com/FRG7700/

Cheers.

Ken

"eddumweer" wrote in message
...
I only have a bad pdf of it, so that could be the problem.

Indeed check if there are 7 of the same type of transistor there and
you
can
try it on 2 way's. You can change them one with another or if it is a
leddisplay get the suspected transistor out of it then it must go dark.
If
the problem is from pin 25 then check with an oscilloscoop if it's
switching
right, looking to another pin with the same function for another
segment.

Good luck PP

"Henry Kolesnik" schreef in bericht
m...
Peter
Thanks for the tip but I had previously checked the voltages on the
transistors you mention and all are B +4.44, E +4.58 and C -22.4
volts.
I
discounted them as being the problem because there's only five and
there
are seven segments. My guess is that these transistors are the
individual
digit drivers as there are five digits and the segments are muxed
from
the
msm5524. If I look closely at the copy of a copy many times over of
the
schematic I can see where a prevoius owner made notes indicating that
the
center segment is driven by pin 25. Any more tips appreciated. As
you
can tell I'm out of my league with this kind of stuff.

--

73
Hank WD5JFR
"eddumweer" wrote in message
...
Check the segment transistors position Q1052-Q1056 (2sa733a-q)

One of them will probably be shorted. The signals for the
transistors
are
coming from ic msm5524 controlling the frequency and time display.

Greetings Peter

"Henry Kolesnik" schreef in bericht
m...
It's a five digit display made of seven segment digits. The center
or
"G" segment doesn't blank when zero is displayed so zero looks like
an
eight. It has leading zero suppression and instead of the zero
being
totally suppressed the center segment appears as a minus sign.

--

73
Hank WD5JFR
"dxAce" wrote in message
...


Henry Kolesnik wrote:

All the center segments stay bright, no blinking.

OK, what is it you wish to blank then? I owned a FRG-7700 for
several
years.
What exactly do you mean by 'center segments'?


tnx

--

73
Hank WD5JFR
"dxAce" wrote in message
...


Henry Kolesnik wrote:

The freqency /time display doesn't blank any of the center
segments
on
either time or frequency function. Any suggestions on a fix
appreciated.
The serial number is 59,800 and I wonder if anyone can tell me
if
this is
an
early or late model?
tnx

Blank or blink?



--

73
Hank WD5JFR