This is the problem that I have got with my SG-230.
I purchased it new myself. My PCB board is an Q50102000-E. it is what they
call the newer version, after the year 2000.

My manual is a Revised: November 2000. The Document number for the
schematic, Q30102000E Rev: A Dated February 17, 1992. It looks to me to be
the wrong schematic for my PCB board. Maybe some one might know if it is or
not or have the correct one that they can send me?

All it says about the diodes is that they are either D5, D7, D9 etc. It
doesn't say what they are.

73 Andy



"Cecil Moore" wrote in message
. ..
Andy wrote:
Cecil,

I had a look at the 1N4148, they are 2-pin.

The diodes in mine are Surface mount 3-pin.

Are the 1N4148 diodes for the old version board, before year 2000?

Yes, my manual is copyright 1994.

My board is the newer version, after year 2000

What does your schematic say about those diodes?
--
73, Cecil http://www.w5dxp.com

Andy wrote:
My manual is a Revised: November 2000. The Document number for the
schematic, Q30102000E Rev: A Dated February 17, 1992. It looks to me to be
the wrong schematic for my PCB board. Maybe some one might know if it is or
not or have the correct one that they can send me?

This one is copyrighted Nov. 2000

www.sgcworld.com/Publications/Manuals/230man.pdf

All it says about the diodes is that they are either D5, D7, D9 etc. It
doesn't say what they are.

Yes, it doesn't say but if it were me, I would replace the
blown diodes with 1N4148's (assuming discrete diodes will
fit in the SMD pad space).
--
73, Cecil http://www.w5dxp.com

Yes, that is exactly the same manual as mine.
How would I connect the 1N4148 2-pin to the 3 pads that are under the SM
3-pin diodes, will this even work?

If it is possible I would have to mount them vertical.

73 Andy


"Cecil Moore" wrote in message
. ..
Andy wrote:
My manual is a Revised: November 2000. The Document number for the
schematic, Q30102000E Rev: A Dated February 17, 1992. It looks to me to
be the wrong schematic for my PCB board. Maybe some one might know if it
is or not or have the correct one that they can send me?

This one is copyrighted Nov. 2000

www.sgcworld.com/Publications/Manuals/230man.pdf

All it says about the diodes is that they are either D5, D7, D9 etc. It
doesn't say what they are.

Yes, it doesn't say but if it were me, I would replace the
blown diodes with 1N4148's (assuming discrete diodes will
fit in the SMD pad space).
--
73, Cecil http://www.w5dxp.com

Andy wrote:
Yes, that is exactly the same manual as mine.
How would I connect the 1N4148 2-pin to the 3 pads that are under the SM
3-pin diodes, will this even work?

I'm pretty sure it would work if you get the pads right.
One is probably grounded. One is probably the cathode.
One is probably the anode. You should be able to figure
out which is which using a digital ohm-meter.
--
73, Cecil http://www.w5dxp.com

I found this just a few minutes ago, on a web site.
The diodes are in a small 3-leaded SM package. Looking down at the
package with it oriented so that the single lead is on top, the
cathode is the top tab and the anode is the left tab on the bottom.

It looks like the bottom right out of the two is not used.
Wonder if anyone can confirm the above?

73 Andy



"Cecil Moore" wrote in message
t...
Andy wrote:
Yes, that is exactly the same manual as mine.
How would I connect the 1N4148 2-pin to the 3 pads that are under the SM
3-pin diodes, will this even work?

I'm pretty sure it would work if you get the pads right.
One is probably grounded. One is probably the cathode.
One is probably the anode. You should be able to figure
out which is which using a digital ohm-meter.
--
73, Cecil http://www.w5dxp.com

In article ,
Andy wrote:

I found this just a few minutes ago, on a web site.
The diodes are in a small 3-leaded SM package. Looking down at the
package with it oriented so that the single lead is on top, the
cathode is the top tab and the anode is the left tab on the bottom.

It looks like the bottom right out of the two is not used.
Wonder if anyone can confirm the above?

That's consistent with what I see in the data sheets for the
surface-mount (SOT-23) switching diodes of type 914 and 4148.

--
Dave Platt AE6EO
Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!

All it says about the diodes is that they are either D5, D7, D9 etc. It
doesn't say what they are.

Yes, it doesn't say but if it were me, I would replace the
blown diodes with 1N4148's (assuming discrete diodes will
fit in the SMD pad space).

I wonder whether these diodes might not be MMBD4148 or some such?
These are 1N4148-type fast switching diodes in an 3-pin SOT323
surface-mount package.

Mouser and Digi-Key carry several variants of these. The MCC versions
are $.10-$.15 each in onesies and are good to 75V, 150 mA. The Diodes
INc. versions are around half a buck each in onesies, and are good to
75V, 200 mW. I'm not sure whether you'd want apples, or oranges :-)

--
Dave Platt AE6EO
Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!

In my SG-230, it says 5DL on the top of diode. Don't know if that is an ID:
code of sorts.

73 Andy


"Dave Platt" wrote in message
...
All it says about the diodes is that they are either D5, D7, D9 etc. It
doesn't say what they are.

Yes, it doesn't say but if it were me, I would replace the
blown diodes with 1N4148's (assuming discrete diodes will
fit in the SMD pad space).

I wonder whether these diodes might not be MMBD4148 or some such?
These are 1N4148-type fast switching diodes in an 3-pin SOT323
surface-mount package.

Mouser and Digi-Key carry several variants of these. The MCC versions
are $.10-$.15 each in onesies and are good to 75V, 150 mA. The Diodes
INc. versions are around half a buck each in onesies, and are good to
75V, 200 mW. I'm not sure whether you'd want apples, or oranges :-)

--
Dave Platt AE6EO
Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!

In my SG-230, it says 5DL on the top of diode. Don't know if that is an ID:
code of sorts.

Yes, that's an ID code.

According to one set of notes I've found, Fairchild use 5D as the code
for an MMBD914, which is a fast switching diode similar to the 4148,
in a 3-lead SOT-23 case. The MMBD4148 would have a 5H code. The two
parts look *very* similar on the data sheets, and from what I've seen
in practice they're interchangeable in most applications.

If this is what you've got, then the pinout is as follows: if you
look down from the top of the diode, with the two-leaded side on the
left and the one-leaded side on the right: pin 1 at the top left is
the diode's anode, pin 3 at the right center is the diode's cathode,
and pin 2 at the lower left is not connected to the diode.

The pinouts are the same for the MMBD914 and MMBD4148.

--
Dave Platt AE6EO
Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!

I have checked diodes D4, D5, D6, D8, D9 and D10 and all of them check out
OK.

All 5 LED's are lit and stay lit when I key and de-key the transceiver.
There is no clicking of the relays.



In the SGC Smartuner troubleshooting that can be found here
http://www.sgcworld.com/Publications...oubleshoot.pdf it says,



For newer SG-230's and other SGC antenna couplers:

1. If LEDs do not light, RF sense diodes and bypass capacitors are suspect.
Also

check Q1 (ZN2222) and CPU chip (68HC711).



2. If LEDs do light and coupler does not initiate tuning, check the CPU
chip. On rare

occasions, the mixer A1 may fail. Verify if you have clock signal on the
output of U3

(74HC393) chip. Verify DC voltage at U11, Pin 1 during transmit. Check R1
and if

no voltage is present, check all 4 sensing signal inputs to the CPU chip -
FWD, REV,

PHASE, IMPEDANCE. If you have an input signal, you should see the
appropriate

LED light. Also verify RF PWR signal is present.



How do I check the mixer A1 to find out if it's working?



What equipment would I need to check for a clock signal on the output of the
74HC393 chip?



What or where is U11 and how can I determine what one is pin 1?



R1 has voltage.



73 Andy





"Dave Platt" wrote in message
...
In my SG-230, it says 5DL on the top of diode. Don't know if that is an
ID:
code of sorts.

Yes, that's an ID code.

According to one set of notes I've found, Fairchild use 5D as the code
for an MMBD914, which is a fast switching diode similar to the 4148,
in a 3-lead SOT-23 case. The MMBD4148 would have a 5H code. The two
parts look *very* similar on the data sheets, and from what I've seen
in practice they're interchangeable in most applications.

If this is what you've got, then the pinout is as follows: if you
look down from the top of the diode, with the two-leaded side on the
left and the one-leaded side on the right: pin 1 at the top left is
the diode's anode, pin 3 at the right center is the diode's cathode,
and pin 2 at the lower left is not connected to the diode.

The pinouts are the same for the MMBD914 and MMBD4148.

--
Dave Platt AE6EO
Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!