Re: Lifetime resistor supply
Did you try the magnet test to make sure they aren't the tin coated steel connecting lead types?
?
Got caught once, they went in the bin quick smart.
--
Terry VK5TM
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Re: Lifetime resistor supply
Thank you for the information.?
Ted
On Sat, Mar 22, 2025 at 15:24 chuck adams via <chuck.adams.phd= [email protected]> wrote: The blue body is for the metal film resistors and they are 1% precision.
The tan body is for the carbon film resistors and they are 5% precision.
On 3/22/25 15:10, Ted via wrote:
> Other than being difficult to read, is there any significant
> electrical difference between blue and brown for the color?
>
> Ted
>
>
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Re: Lifetime resistor supply
The blue body is for the metal film resistors and they are 1% precision.
The tan body is for the carbon film resistors and they are 5% precision.
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On 3/22/25 15:10, Ted via groups.io wrote: Other than being difficult to read, is there any significant electrical difference between blue and brown for the color?
Ted
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Re: Lifetime resistor supply
Other than being difficult to read, is there any significant electrical difference between blue and brown for the color?
Ted
On Sat, Mar 22, 2025 at 14:23 chuck adams via <chuck.adams.phd= [email protected]> wrote: > ... snip? snip ...
> I measure all resistors before putting them in circuit, but checking
> on values /after/ a resistor has been soldered into a circuit can be a
> nuisance if it's a metal film, as they don't always comply with visual
> checks and, as we all know, measuring resistors in-circuit usually
> doesn't go as well as it does with tube circuits. That's one thing
> about tubes that I like!
> Dave
> AA7EE
I showed a cheap component tester in my last video.? I use it to measure
everything before I put
it into a project.? The tester doesn't have to be accurate all the
time.? It's just to make sure
I haven't forgotten the color code etc.? Saves a lot of time searching
later for a part that
isn't what it is supposed to be.
Sometimes you even find a bad part.? Who'd have thunk?? Glad to see that
I'm not alone in
the Universe for measuring critters.
"Number 5 needs data."
chuck, aa7fo
PS.? Your filaments in your tubes consume more power that I do on the
air.? :-)
> ._,_._,_
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Re: Lifetime resistor supply
... snip? snip ... I measure all resistors before putting them in circuit, but checking on values /after/ a resistor has been soldered into a circuit can be a nuisance if it's a metal film, as they don't always comply with visual checks and, as we all know, measuring resistors in-circuit usually doesn't go as well as it does with tube circuits. That's one thing about tubes that I like!
Dave
AA7EE I showed a cheap component tester in my last video.? I use it to measure everything before I put it into a project.? The tester doesn't have to be accurate all the time.? It's just to make sure I haven't forgotten the color code etc.? Saves a lot of time searching later for a part that isn't what it is supposed to be. Sometimes you even find a bad part.? Who'd have thunk?? Glad to see that I'm not alone in the Universe for measuring critters. "Number 5 needs data." chuck, aa7fo PS.? Your filaments in your tubes consume more power that I do on the air.? :-) ._,_._,_
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Re: Lifetime resistor supply
On Sat, Mar 22, 2025 at 09:28 AM, chuck adams wrote:
But Dave,? didn't you find that the metal films produced less RF noise?? Of course, when
you need a 100ohm resistor, all you have is 91ohms........
That's my understanding Chuck; that the metal film resistors produce less noise. I haven't done a comparison, or any measuring though, so haven't actually noticed it.
?
I measure all resistors before putting them in circuit, but checking on values after a resistor has been soldered into a circuit can be a nuisance if it's a metal film, as they don't always comply with visual checks and, as we all know, measuring resistors in-circuit usually doesn't go as well as it does with tube circuits. That's one thing about tubes that I like!
?
Dave
AA7EE
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On Sun, Mar 16, 2025 at 02:05 AM, Walter Thomas/K3ASW wrote:
G3URR crystal measurement method
?
Mike,
?
In one of his more recent postings to his website (~last two or three years), W7ZOI changed the oscillator's emitter resistor from 1K to 3k3 to reduce drive to the crystal under test and noted more stable readings when doing the measurements.
?
Regards,
Walt ? K3ASW
?
When I added my message last night, I forgot to add that Wes adding Errata about that 3k3 resistor.? Not only the resistor changed but some of the formulas used in the Experimental Methods in RF Design book.
?
?
?
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I purchased this crimper set a couple years ago and it covers a lot of bases.
?
?
I admit to not doing JST connectors, but I have been able to satisfactorily do any crimp connector I have come across.
?
And like others have said, there is a little fiddling sometimes, and if I was doing thousands, and trying to minimize production time I would buy the proper tool.
?
That usually isn't the case on our benches though.
?
I also have another rachet crimper set that does just about any size of coax connector.
Powerwerx also has some nice sets that are not insanely priced.
?
Happy tinkering.
?
-Albert
KI4ORI
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Re: Lifetime resistor supply
I believe this is the link:
Mike N2MS
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On 03/22/2025 12:23 PM EDT chuck adams via groups.io <chuck.adams.phd@...> wrote:
Ask and you shall receive.? Amazon (let's make Jeff richer site) and
search for
"1/4W carbon film resistor kit" and you get a large selection that I
have done
gone through.? I just picked this.
FYI
gold precision band for 5%
chuck, aa7fo
On 3/22/25 09:14, k6whp via groups.io wrote:
Thank you. These sound ideal as -- I am sure you know -- the blue
colored ones are the devil to distinguish green, red, blue, etc.
If you care to share a link, I'm sure others would appreciate same.
--
William, k6whp
--------------------
"Cheer up, things could get worse. So I cheered up and things got worse."
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I'm sorry, one more point.
With so many resistors, you've got a serious problem.? Storage.
I use #6 coin envelopes that I got from Staples a long time ago
in a galaxy far away (Dallas).? 250 envelopes in a box.? I checked
yesterday online and I could not believe the current cost.? Well,
maybe I can.
The resistors fit perfectly and easy to label and easy to store in
a drawer or plastic shoe like box the right size.
FYI
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Re: Lifetime resistor supply
But Dave,? didn't you find that the metal films produced less RF noise?? Of course, when
you need a 100ohm resistor, all you have is 91ohms........
chuck, aa7fo
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On 3/22/25 09:24, davidgeorgerichards via groups.io wrote: You did good with those carbon film resistors Chuck. Most of the resistors in my stash are the now ubiquitous 1% metal film types. Nice and stable, tight tolerance. Agreeable in every way, apart from the color codes on the blue bodies, which are so dang hard to read! I know I'm only saying something that has already been thought and said by 50 million homebrewers the world over but man, these blue-bodied resistors really are the scourge of homebrewers. And I have close to a lifetime supply of them. Aaaargh!
As I said, you did good with the tan-bodied carbon film resistors.
Dave
AA7EE
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Re: Lifetime resistor supply
On 3/22/25 09:23, chuck adams via groups.io wrote: Ask and you shall receive.? Amazon (let's make Jeff richer site) and search for
"1/4W carbon film resistor kit" and you get a large selection that I have done
gone through. I have not gone through.?? My English is better than that.? Speed typing sucks.
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Re: Lifetime resistor supply
You did good with those carbon film resistors Chuck. Most of the resistors in my stash are the now ubiquitous 1% metal film types. Nice and stable, tight tolerance. Agreeable in every way, apart from the color codes on the blue bodies, which are so dang hard to read! I know I'm only saying something that has already been thought and said by 50 million homebrewers the world over but man, these blue-bodied resistors really are the scourge of homebrewers. And I have close to a lifetime supply of them. Aaaargh!
?
As I said, you did good with the tan-bodied carbon film resistors.
?
Dave
AA7EE
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Re: Lifetime resistor supply
Ask and you shall receive.? Amazon (let's make Jeff richer site) and search for
"1/4W carbon film resistor kit" and you get a large selection that I have done
gone through.? I just picked this.
FYI
gold precision band for 5%
chuck, aa7fo
toggle quoted message
Show quoted text
On 3/22/25 09:14, k6whp via groups.io wrote: Thank you. These sound ideal as -- I am sure you know -- the blue colored ones are the devil to distinguish green, red, blue, etc.
If you care to share a link, I'm sure others would appreciate same.
--
William, k6whp
--------------------
"Cheer up, things could get worse. So I cheered up and things got worse."
|
Re: Manhattan Construction Classes
I'm about to post my second video in an hour.? In it there is a
cheap Chinese component tester.? Find them on amazon and all your
favorite critter suppliers online.? Attached photo.? I have one
with the plastic case to prevent a disaster on a workbench with
a copious supply of clipped component leads.? :-)
Went over to the other desk, took the critter and I have a pill
bottle with a long strip of diodes and took four of them and
measured them.? Surprise.? The voltage drop was 253mV.? Looked
with jewelers loupe and the band is green.? They are Ge diodes.
I thought they were 1N4148s.? Need to label the bottle.
The voltage drop measurements show 3 decimal places and I can
see a +-1 mV change.? Not sure that is enough, but it may be.
I'll do a finer measurement in a video, but in the meantime
maybe someone else can do a finer report for the audience.
It'd starting point for testing.? I'd use a solderless
protoboard and a battery, a current limiting resistor
and power up diodes and measure the voltage drop at a low
current level, since that is where they are going to be
used in a ring diode mixer.
chuck, aa7fo
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On 3/22/25 08:23, Alan N8WQ via groups.io wrote: Hi Chuck,
Can I make a recommendation for your Manhattan Construction Classes?
Can you make a video about matching diodes?
Thanks!
Alan, N8WQ
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Re: Lifetime resistor supply
Thank you. These sound ideal as -- I am sure you know -- the blue colored ones are the devil to distinguish green, red, blue, etc.
?
If you care to share a link, I'm sure others would appreciate same.
?
--
William, k6whp
--------------------
"Cheer up, things could get worse. So I cheered up and things got worse."
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Re: Lifetime resistor supply
William,
Four strips, so they are marked for precision range.
Body is tan, typical for carbon film resistors.
FYI
chuck, aa7fo
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On 3/22/25 08:11, k6whp via groups.io wrote: Are they four stripe or five stripe coded and are the resistor bodies blue or tan?
--
William, k6whp
--------------------
"Cheer up, things could get worse. So I cheered up and things got worse."
|
Manhattan Construction Classes
Hi Chuck,
Can I make a recommendation for your Manhattan Construction Classes?
Can you make a video about matching diodes?
Thanks!
Alan, N8WQ
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Re: Lifetime resistor supply
Are they four stripe or five stripe coded and are the resistor bodies blue or tan??
--
William, k6whp
--------------------
"Cheer up, things could get worse. So I cheered up and things got worse."
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Crystal Experiment for Beginners and Experts Alike
I'm in the middle of a big project, but I ran across a need for the following
and I'm on a side excursion in the lab for a few hours and I thought some in
the group might be interested in trying this.? That is, if you are bored.
In EMRFD by Wes Hayward, W7ZOI, Chapter 1, Page 1.11, Figure 1.15 is a
schematic for a simple Colpitts crystal oscillator.? And if you don't have
a copy of EMRFD, shame on you.? :-)? BTW.? The book came with a CD with his
RF Design book, that I scanned in and Wes used for the second printing.
OK, I got lost.? Looks like book is no longer in print that I can tell.
Copy on amazon for $92!!!? I don't think anyone will buy it at that price.? IMHO.
<>
We all could get rich!
Project:? Build the critter.? Use a socket for the crystal, but also use a socket
for the transistor.? Model the circuit using LTSpice and/or ngspice and use
K8IQY.com for the crystal parameters, if you don't already have some you measured.
Experiment with output levels for different frequencies and different transistors.
I'm building one as we speak to add to the set of tools to test crystals and also
to test transistors from China.? Some one mentioned, and I apologize for not looking
up the name and call, measuring the noise figure.? Care to give the group a lesson?
It would be appreciated.? I'm going to go through my pile of different sets to
eliminate any future problems.
Sharing,
chuck, aa7fo
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k6whp
Alan N8WQ