Your latest purchase

I'm no battery expert, but I believe lithium batteries have to be charged within about 0.1V of specs, and to certain current limits. Otherwise, fireworks. I advise against a voltage divider.

I don't think a CR2032 3V lithium manganese dioxide button battery is rechargeable, but there is a lithium ion button type that is.

From wikipedia:

Rechargeable variants

Most button cell batteries are not rechargeable due to the inferior capacity and/or high self-discharge rate of rechargeable batteries. There are a few rechargeable button cell batteries, such as lithium-ion rechargeable batteries intended to replace CR-series lithium manganese dioxide batteries in devices with relatively high current consumption or some devices with solar panels which can be used to keep the battery charged under certain circumstances.

Bought a pair of these beauties so to have a back-up pair for my ham radio transceiver. A pair of these output 100 watts of RF power. These were NOS (new old stock) and I got a pair with matching date codes of 8813 which is pretty recent for these tubes. Only made new in China these days with mixed opinions on their quality and performance. So the NOS trade is getting pretty pricey for the more desirable tubes. These usually go for around $60-80 a pair in unused and tested condition and I waited for around 3 months to find this pair going for $30 buy it now. He had six available but between two of us they sold out in five mins. E-bay can be great if you are patient and know what you are buying.

Here is similar listing to show what they look like. They run at around 900 volts DC at 200ma on plates.

http://www.ebay.com/itm/RCA-6146B-8298A-Tube-/360375850725?pt=Vintage_Electronics_R2&hash=item53e81316e5

OTOH, oh well, at least they were cheap and
OTOH fireworks you say? Obviously an outdoor activity but I sorely miss my bags of KClO4 and aluminum dust.

GoForSmoke:
OTOH, oh well, at least they were cheap and
OTOH fireworks you say? Obviously an outdoor activity but I sorely miss my bags of KClO4 and aluminum dust.

Ah, an old basement bomber! That stuff would probably get you thrown in jail these days. We tended to use magnesium and just a bit of antimony disulfide.

OK, no drug dealing or latest crack recipes in the 'Your latest purchase' thread. :wink:

so what you need is a kilo, a pneumatic ram, and a arch welder ...

retrolefty:

[quote author=Jack Christensen link=topic=91399.msg733830#msg733830 date=1332380677]

GoForSmoke:
OTOH, oh well, at least they were cheap and
OTOH fireworks you say? Obviously an outdoor activity but I sorely miss my bags of KClO4 and aluminum dust.

Ah, an old basement bomber! That stuff would probably get you thrown in jail these days. We tended to use magnesium and just a bit of antimony disulfide.

OK, no drug dealing or latest crack recipes in the 'Your latest purchase' thread. :wink:
[/quote]

Uhhh, nope, not drugs, no way, uh-uh. Fireworks as in pyrotechnics back in the old days (all before 1990) and NO formulas.

However if once these button cells are drained they might get one last bang, well July 4th is coming up.

Ditto, but regardless, this thread probably has the klaxons going off in that little room in the back of the CO.

Just because you're paranoid doesn't mean that they're not out to get you :fearful:

Went to Goodwill yesterday (Saturday), and found a bashed up (but possibly serviceable, given a little TLC) styrofoam R/C 3-channel plane (electric). She didn't come with a transmitter, though. She needs more than a bit of work, but it's styrofoam, so nothing a little white glue can't fix. Heck, for the $3.50 USD it cost me, the servos, ESC and motor are worth it even if she never flies again. Then again, maybe she'll become a future UAV?

Could you fit the good parts into another model airframe? Still need the transmitter/controller and from what I've seen, that's the expensive part.

GoForSmoke:
Could you fit the good parts into another model airframe? Still need the transmitter/controller and from what I've seen, that's the expensive part.

Actually, the airframe isn't in too bad a shape; it is all styrofoam. The main problems seem to be in the rear stabilizer: One of the horizontal fins is cracked and just needs a bit of re-gluing, and the movable rudder flap has come loose (the flaps, horizontal and vertical, are attached via these small strips of plastic, which have cracked in half). It also needs a new front landing gear.

I have a couple of transmitters/receivers, though I don't recall if they are 3-channel (I know for sure one is a 2-channel kit). If I take it the UAV route, though, I might just set up some kind of UHF telemetry/control system, with Ardupilot and the rest on-board, and forgo a regular R/C setup.

One of the bad thing about the plane is that everything seems glued in-place (and it looks like it was with epoxy or something); removal of the components and reuse may or may not be possible... :frowning:

In no way electronics related, but I just wanted to have it :wink:

Note the matching avatar icon.

Wait, I forgot... there's some electronics stuff.

A couple of folk in the German board wanted to have some F-RAM chips and I just happened to order stuff at mouser anyway. So these are not exactly mine, but I made the purchase :wink:

Ramtron FM24W256-G IĀ²C FRAM 256k 3-5V

My latest purchase is a filco majestouch tenkeyless keyboard with brown cherries. The price is hefty but I figure I should have bought such a keyboard ten years ago. This thing is worth the pricetag. I bought it basically for the "tenkeyless" feature to get the mouse closer to the keyboard. However typing with this is a completely different experience. Once you are used to it all "standard" keyboards feel like cheap crap.

9 inch trinatron tv, we wanted a tv for the spare room, I wanted something small so I didnt have to find room for it so I got this for 6 bucks at goodwill. I was hoping that it would also double as a computer monitor for my apple // but when I plugged it in, its all kinds of blurry on the text ... which is very surprising considering I can darn near read the fine print on TV commercial disclaimers, and the screen is ultra sharp.

maybe I need to go in there and investigate

Picked up a Systron-Donner 7015 frequency counter, some internal component photos posted here: https://plus.google.com/photos/114770676851387917990/albums/5723984429278618033

Still works exceptionally well and appears to be quite accurate. Not too shabby for a piece of kit from 1970. I picked it up more for sentimental reasons than for any practical purposes (Grandfather was a ham operator and had a similar unit in his radio shed). It's fairly large and noisy, but there's something about nixies that I absolutely love.

A couple of questions for the EE veterans on the board... First, I imagine that this was quite an expensive piece of equipment in the 70s. Does anyone happen to remember what one of these went for back then? Second, the unit is capable of measuring frequencies up to 500MHz; what kind of signals would this have been useful for at the time this was released? Based upon the amount of corrosion on the 500MHz terminal it does not appear to have gotten much use.

I use an IBM Model M.

Compared to it, all "standard" keyboards -are- crap (especially the mac bluetooth keyboard - I hate it that thing)...

cr0sh:
I use an IBM Model M.

Also doubles as an excellent personal defense weapon. That keyboard's a beast :stuck_out_tongue:

Huh. I really like my low-profile Mac keyboard (I have the wired one.)

Recent Mouser order: 40pin DIP sockets, a couple "new" TI Launchpads, Microchip 10F322 eval board, tips for the new soldering iron, a couple ATmega328 (NOT "328P") to look at optiboot issues, and some of the new FTDI FT230
USB/Serial chips (half the pins and half the price. More or less.)

I was considering a Model M as well. However I did not find a Model M with german layout and the tenkeyless feature. Thus I settled for the Filco. I know that the Model M is even better but I love tenkeyless.