David,
Welcome to the world of Elecraft.
Do stay around - no harm done. If you are using Nabble to respond, know
that those of us on the official Elecraft reflector see only what you
wrote and none of what you are referring to - unless you copy a bit of
it in your post. Nabble is not
Wow, I'm glad I found this post. I just completed building the control board
for my K2, and found the resistance on U6 pins 29 and 30 to be 96.4K. I
didn't really think it was an issue, but it is always nice to have someone
else confirm it. All other resistance checks were within specs.
What post? Your post makes no sense without a bit of reference material.
Sorry, but I subscribe to the Elecraft reflector and do not have time
for threaded conversations that might appear on nabble.
Please copy a bit of your referenced text in the future.
73,
Don W3FPR
On 7/13/2014 10:46
Sorry Don, I'm new to the the Reflector, and didn't mean to create a problem.
I figured since I was replying to a particular thread, it would all make
sense. I guess I was wrong. So hopefully, here is some reference material.
If I screw it up this time, just ignore everything, and I'll go away
I have some questions on the results of my check.
U6 pin 29 should read between 70 and 90k, I'm reading 96k.
U6 pin 30 should read between 70 and 90k, I'm reading 97k.
U8 pin 15 and 16 should read 100k, I'm not getting a reading at all so I'm
wondering if this is the way my DMM reads infinity.
Ed,
The first two readings are very likely OK, you might re-check by
reversing the leads or putting new batteries in your DMM. The other
possibility is that you are using auto-ranging, and the reading may be a
bit different if you switch to the first fixed range greater than 90k
I don't
Those should be good, Ed. When trying to measure resistance in a circuit
containing semiconductor junctions, DMMs voltage can sometimes alter
readings a bit. You are within 10%.
Many DMMs give no reading at all when seeing an open circuit. What does you
DMM do in resistance scale with the leads
I have just finished the assembly of the K2 Control Board and am doing
resistance checks, as per assembly instructions. Since I have not done
something like this before I am hoping I have interpreted the directions
correctly. The directions say to take measurements with respect to ground. I
Paul,
Yes, you would connect one lead (usually the black one) of your DMM to
ground.
If by no reading you mean infinite resistance (the same thing the
meter displays when the leads are not touching anything), then those two
readings are correct.
The other problem I see is the measurements
Hi Paul WN2K,
What I propose you do is:
1) Set the return/ground/neutral lead - typically the black lead - of
your multimeter, to one of the grounding terminals that you soldered
into the control board using a piece of component lead. The easiest way
for you to do this is to use an alligator
Hi everybody,
I recently started building a K2 and I've just finished the assembly of the
control board. My resistance checks are all within specs except two of them
are
just a little bit off. My readings at pins 29 and 30 of U6 are a little bit
higher than those listed in the table. (I'm
Paul,
Yes, those are OK. They are the DOT and DASH lines to the
microprocessor and have nothing else but U6 on the Control Board to
bring the resistance down.
In general, a 10% deviation from the values listed in the manual are
close enough.
73,
Don W3FPR
Paul Huff wrote:
Hi everybody,
If you get strange readings after reversing the leads try reading the
resistance on pin 21 (8R) and pin 23 (8T) of P2 Look at Appendix B Control
Board. even the best of us occasionally mistake the pin out on
transistors.
Rich,
KE0X
Chuck,
Try reversing your DMM probes - it is possible that no
Hi Everybody.
I have just completed the Control board on #3375 and have a question about
the resistance checks. Specifically the check on U4, OUT
The manual says to look for 3-7 k at this pin ... and I measure 2.48 k with
my DMM. Is this value close enough? Should I be looking for a problem
Jeff,
The reading is a wee bit on the low side, BUT...
The proper answer depends on your DMM. First try reversing the probes, and
try another DMM if you can obtain one (beg or borrow).
Bottom line - know your test instruments and their limitations - only then
can you know whether a problem
15 matches
Mail list logo
