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Re: Lifetime resistor supply
My experience with coated steel is that they rust and the problem with that is it can cause the leads to rust through/break over time - it gets worse if you build something for portable use and use that out in damp/wet weather, regardless of whether you are under cover.
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As for brands, that I can't say off the top of my head as I normally buy a minimum 1000 per value from a wholesaler that supplies to industry , the packaging doesn't have any manufacturer branding on the last lot I bought.
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For smaller quantities you'll be looking at the likes of Digikey, Mouser etc but their resistor kits aren't particularly cheap.
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On Sun, Mar 23, 2025 at 01:59 PM, chuck adams wrote:
Yes, they are the coated steel leads.? Didn't know that would be or was a problem. ?
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Terry VK5TM |
Re: Lifetime resistor supply
As to carbon film resistors generating higher noise than metal film ones: that is true when DC is applied to them. Otherwise (such as in RF attenuators) both types generate only thermal white noise. The excess noise has a "1/f" spectrum, it gets worse the lower the frequency at which it is measured. This is more noticeable below 1 or 10kHz; can be neglected at HF. Daniel Perez LW1ECP |
Re: Lifetime resistor supply
Terry,
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Yes, they are the coated steel leads.? Didn't know that would be or was a problem. I checked and Amazon does have free return policy on them. Is there a particular brand that you found that guarantees the plated copper leads? thanks for the heads up, chuck, aa7fo, education is expensive, no matter how you get it...... On 3/22/25 19:26, Terry VK5TM via groups.io wrote:
Did you try the magnet test to make sure they aren't the tin coated steel connecting lead types? |
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. |
Re: Lifetime resistor supply
The blue body is for the metal film resistors and they are 1% precision.
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The tan body is for the carbon film resistors and they are 5% precision. 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? |
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 ... |
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!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.? :-) ._,_._,_ |
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, whenThat'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!
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Dave
AA7EE |
Re: Crystals
On Sun, Mar 16, 2025 at 02:05 AM, Walter Thomas/K3ASW wrote:
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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Re: JST crimping
I purchased this crimper set a couple years ago and it covers a lot of bases.
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I admit to not doing JST connectors, but I have been able to satisfactorily do any crimp connector I have come across.
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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.
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That usually isn't the case on our benches though.
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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.
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-Albert
KI4ORI |
Re: Lifetime resistor supply
I believe this is the link:
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Mike N2MS On 03/22/2025 12:23 PM EDT chuck adams via groups.io <chuck.adams.phd@...> wrote: |
Resistors
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 |
Re: Lifetime resistor supply
But Dave,? didn't you find that the metal films produced less RF noise?? Of course, when
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you need a 100ohm resistor, all you have is 91ohms........ chuck, aa7fo 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! |
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 forI have not gone through.?? My English is better than that.? Speed typing sucks. |
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!
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As I said, you did good with the tan-bodied carbon film resistors.
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Dave
AA7EE |
Re: Lifetime resistor supply
Ask and you shall receive.? Amazon (let's make Jeff richer site) and search for
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"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. |
Re: Manhattan Construction Classes
I'm about to post my second video in an hour.? In it there is a
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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 On 3/22/25 08:23, Alan N8WQ via groups.io wrote:
Hi Chuck, |
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.
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If you care to share a link, I'm sure others would appreciate same.
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William, k6whp -------------------- "Cheer up, things could get worse. So I cheered up and things got worse." |
Re: Lifetime resistor supply
William,
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Four strips, so they are marked for precision range. Body is tan, typical for carbon film resistors. FYI chuck, aa7fo 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? |
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