According to my schematic Q57 and Q58 are drivers for the 2 LEDs used in the
clock mode to indicate AM or PM. Looks like I'm going to get the scope on
the bench and see what happens on the various segment pins. I've not had
much luck finding the data sheet on the MSM5524, anyone have any?
tnx

--

73
Hank WD5JFR
"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

In article ,
Henry Kolesnik wrote:
According to my schematic Q57 and Q58 are drivers for the 2 LEDs used in the
clock mode to indicate AM or PM. Looks like I'm going to get the scope on
the bench and see what happens on the various segment pins. I've not had
much luck finding the data sheet on the MSM5524, anyone have any?

The service manual for the (Trio)Kenwood R-1000 has a lot on it.
Internal block diagram and pinout. I got the pdf from the mods.dk
site.

Mark Zenier Washington State resident

Thanks Mark I'll go to .dk and get whatever they have.

--

73
Hank WD5JFR
"Mark Zenier" wrote in message
...
In article ,
Henry Kolesnik wrote:
According to my schematic Q57 and Q58 are drivers for the 2 LEDs used in
the
clock mode to indicate AM or PM. Looks like I'm going to get the scope on
the bench and see what happens on the various segment pins. I've not had
much luck finding the data sheet on the MSM5524, anyone have any?

The service manual for the (Trio)Kenwood R-1000 has a lot on it.
Internal block diagram and pinout. I got the pdf from the mods.dk
site.

Mark Zenier Washington State resident