Has anyone on here played with pummer circuits?
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@Stormgren how would you even know of all the components you could possibly need? I have a bunch of capacitors and resistors here, but the list of components is endless. I had never even heard of this chip before now
@MLE_online I mean, it's not going to be an exact science, but resistors, caps, and whatnot come in assortments so that's an easy setup. Cruft extra parts and donations tend to accumulate so that also helps, and sometimes you need to just do a mouser order and group brainstorm stuff that people said "wow, I wish we'd had a $foo sitting around, could have used one the other day to fix a thing" and stock up. Then curate every so often.
I have a pile of stuff personally that's accumulated over the years, so it's hard for me to judge, but any time I order parts, I usually get a couple of extra if it's not too much, ICs don't tend to take up a lot of room.
(The 74AC240 isn't an uncommon logic chip, or at least it didn't used to be)
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@MLE_online @Stormgren I might have one and can send it to you for free, lemme look
@ai6yr @MLE_online I was just doing the same thing here, I would swear I've got some around here I could part with.
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@MLE_online
Presuming the days of Radio Shack et al are long gone (not sure how they could carry the range of possible stock anyway these days)...
AliExpress, is that usable from the US? I've ordered things that have made if from China to W Europe in 6 days....they also have "local" supply options but I'm dubious...
https://www.aliexpress.us/w/wholesale-74AC240.html ?@acesabe yea, i order from aliexpress, and the prices are good, but im not going to mail order a single chip from china
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@MLE_online ...or ask rue to donate ya one for the project and stuff it in a snail mail envelope for free....
@RueNahcMohr you always say canadian mail is extremely slow and unreliable though!
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@MLE_online @Stormgren I might have one and can send it to you for free, lemme look
@ai6yr @Stormgren if you do and can, that would be amazing
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@MLE_online ...or ask rue to donate ya one for the project and stuff it in a snail mail envelope for free....
@RueNahcMohr @MLE_online
Or me. (why I save scrap PCBs with socketed parts) hehe
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@ai6yr @Stormgren if you do and can, that would be amazing
@MLE_online @Stormgren MC1488 quad line driver should work, it's the same thing but 4x instead of 8x.


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@MLE_online @Stormgren MC1488 quad line driver should work, it's the same thing but 4x instead of 8x.


@MLE_online @Stormgren Hmm, I guess don't have the enable. Not sure if that's necessary... I have more I can go look at lol. https://www.ti.com/product/SN74AC240#tech-docs


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@MLE_online @Stormgren MC1488 quad line driver should work, it's the same thing but 4x instead of 8x.


@ai6yr @Stormgren What's enable?
you would know better than me. This is the circuit I was planning to build

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@MLE_online @Stormgren Hmm, I guess don't have the enable. Not sure if that's necessary... I have more I can go look at lol. https://www.ti.com/product/SN74AC240#tech-docs


@ai6yr @MLE_online Yeah, the enable is required to keep the circuit from triggering as long as solar input is present, if I am understanding the circuit correctly.
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@ai6yr @MLE_online Yeah, the enable is required to keep the circuit from triggering as long as solar input is present, if I am understanding the circuit correctly.
@Stormgren @ai6yr oh, an enable pin
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@JohnS_AZ They seem neat!
I guess no one on here has any experience with them though
@MLE_online
What circuit are you going to build? I see quite a few out there. -
@MLE_online
What circuit are you going to build? I see quite a few out there.@JohnS_AZ this one seems simple and easy enough
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@ai6yr @MLE_online Yeah, the enable is required to keep the circuit from triggering as long as solar input is present, if I am understanding the circuit correctly.
@Stormgren @MLE_online Ah, then the ones I have won't work for the enable. Lemme look at my other pile, lol.
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@JohnS_AZ this one seems simple and easy enough
@MLE_online hmmm, I think I have everything except the nicads.
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@MLE_online hmmm, I think I have everything except the nicads.
@JohnS_AZ I am planning to just use a couple supercaps in place of the batteries
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@Stormgren @MLE_online Ah, then the ones I have won't work for the enable. Lemme look at my other pile, lol.
@Stormgren @MLE_online look! DM the address to send them to. Lemme find some static safe foam and a little box

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The modern online retail economy sucks!
I need one 74AC240 chip for this. I could order a pack of 10 of them from Amazon (yuck) for $12.25 + $6.99 shipping, a single one from ebay for $2.50 + $12.50 shipping, a pack of 10 of them from ebay for $4.99 + $5.20 shipping, or one for $2 + $10 shipping from Mouser.
UGH
@MLE_online FWIW, Mouser does have a somewhat hidden economy shipping option that’s $6. But yeah, still bananas for a single part.
I’ve been doing inventory on my parts and it occurs to me that I have a lot of extra stock I could share, if only there were some way to do it. I’ve thought it would be neat to have some kind of parts-share site that would allow you to find someone local who has an extra chip or 50K pot or whatever. I think safety might be an issue for sharing mailing addresses. I dunno.
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@Stormgren @MLE_online look! DM the address to send them to. Lemme find some static safe foam and a little box

@Stormgren @MLE_online Four enough? (not that I have ever used these once in the 20? years they have been in my garage).
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@Stormgren @MLE_online Four enough? (not that I have ever used these once in the 20? years they have been in my garage).
@ai6yr ya, that's plenty!