[Elecraft] K1 Filter Board Test Points ?

Sun Mar 23 10:44:01 2003

Hi again Bill! See for my comments behind your messurments!
----- Original Message -----=20
From: "William Carter" <[email protected]>
To: "Morrow, Michael A." <[email protected]>; <[email protected]>
Sent: Sunday, March 23, 2003 1:29 PM
Subject: RE: [Elecraft] K1 Filter Board Test Points ?


> Mike=20
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> Thanks for the response.  Please allow me to be a
> little more precise.
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> P1 pin1, P1 pin2 00.0   ***** OK ******
> P1 pin3, P1 pin4 .0L  ***** OK ******
> P2 pin2, P2 pin4 1.201 **** MY VALUE HERE IS 138Kohms **** WHAT DOES =
OTHERS HAVE ????
> P3 pin1, P3 pin3 .0L  ***** OK *****
> P3 pin8, P3 pin6 .0L *****OK *****
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> Sorry, I am new to even multimeters.  My meter comes
> up .oL and indicates a change by showing oo.o why it
> says .oL on some not sure.
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> T1 leads 1,2 read 00.0
> T1 leads 3,4 read 00.0
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> T2 leads 1,2 read 00.0
> T2 leads 3,4 read 00.0
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> I did a continuity check,=20
> T1 leads 1,2 continuity yes.
> T1 leads 3,4 continuity yes.
> note 1,3 or 2,4 continuity no.
***** ALL T1 READINGS ABOVE OK *****
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> T2 has a problem.  All combinations show continuity. ***** THIS IS OK =
IF MESSURED AFTER SOLDERING TO PCB SINCE LEAD 1 AND 4 ARE SHORTED =
TOGHETHER TO GROUND -*****=20
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> A.  I need to buy more toroid wire, do you know where
> I can get a spool of red and green #26.  I think a
> good investment.
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> B. I should remove U1 before I de-solder.
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> I tried to remove coating on toroid via solder iron,
> someone told me to use bic lighter, steel wool or fine
> sand paper.
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> Maybe before I solder anymore toroids I should check
> them?  Continuity and ohms????
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> Thanks so much for your help and continued tips.  I
> just can't pay to have someone build it.  I will learn
> this if it kills me!
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> Besides making sure all components in correct place, I
> guess do continuity checks on board to look for solder
> joins.  To the eye it looks great.  I checked all
> components again - fine.  I will try to trace say a P1
> Pin point via schematic and look for continuity and
> solder joints.
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> 73
> Bill KG4FXG
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> --- "Morrow, Michael A." <[email protected]> wrote:
> > Bill wrote of the KFL1-4:
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> > > Problems with P1,P2,P3 test points.
> > >=20
> > > P1 pin 1, P1 pin 2 reads 0 (nothing)
> > > P1 pin 3, P1 pin 4 reads 0
> > > P2 pin 2, P2 pin 4 reads 1.212 m
> > > P3 pin 1, P3 pin 3 reads 0
> > > P3 pin 8, P3 pin 6 reads 0
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> > As Tom noted, it's very hard to tell whether the "0
> > (nothing)" you report is
> > meant to tell us whether you mean that a SHORTED
> > (zero ohm) condition is
> > being shown by your ohm-meter, or an OPEN (infinite
> > or very high ohm)
> > condition is being shown.
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> > If "0" indicated above actually means you have a
> > OPEN condition between the
> > test points, then ALL the values you report above
> > are OK except for:
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> > > P1 pin 1, P1 pin 2 reads 0 (nothing)
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> > Here, there should be almost zero ohms (SHORT) shown
> > by your meter.  If not,
> > then you need to check if there's near zero ohms
> > shown between the PCB
> > solder pads for the green winding (terminals 1 and
> > 2) on T1.  If there is
> > instead a high resistance at these two points on the
> > PCB, then you've likely
> > not adequately removed the insulation from and
> > tinned T1's green leads.  You
> > should probably make the same checks between the
> > solder pads for the red
> > windings, then the green windings, on ALL toroids on
> > the PCB.  There should
> > be a short shown in EVERY case.
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> > On the other hand, if you really really really meant
> > that a short in being
> > shown with
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> > > P1 pin 3, P1 pin 4 reads 0
> > > P3 pin 1, P3 pin 3 reads 0
> > > P3 pin 8, P3 pin 6 reads 0
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> > then you've got some unwanted solder bridges in
> > three different circuits,
> > and the value you reported with
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> > > P1 pin 1, P1 pin 2 reads 0 (nothing)
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> > is OK.
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> > These are less likely, which is why I think you're
> > actually indicating high
> > or open resistance rather than the "0" ohms you
> > report.
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> > 73,
> > Mike / KK5F
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> =3D=3D=3D=3D=3D
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