Cool! I haven't seen a 160 before, nor red nixies. Not a bad price either. Does it need any work? Looks pretty good.
Seems to work fine on all ranges I have tried. There is a hand written note on the bottom that it was reading 0.3% high on the 100 mv range, the note is dated 18 Sept, 1988. I had a quick peak inside, I see some chips dated 1973.
The meter is very clean inside and out. There is an "Environment Canada" asset tag on the back so we know who has always owned it. It was listed for $50.00, I offered 25, they countered with 35 and I countered back with my original 25(I know, rather cheeky of me) but I really only wanted it for fun. Now that I have it here I think it is probably worth a little more then I paid.
You countered with the same amount as your prior offer? That's amazing. I figured one would get the instant silent treatment in return. Fascinating.
You countered with the same amount as your prior offer? That's amazing. I figured one would get the instant silent treatment in return. Fascinating.
Well I have received a near instant decline when trying it before. I always add a note with my offer - in this case I said I could only justify the 25 because I was buying it purely for fun. I also said that if it wasn't enough I understood. I'm never trying to make anyone angry and I never mind if they don't accept. The offer was good for 48 hours and with a few hours left the seller accepted. I guess they had no other offers. It may have helped the item was located in Canada. A lot of American's seem to avoid auctions in Canada so every now and then I actually buy something in country.
It is looking like all ranges are giving stable readings that look to be correct but I haven't verified what % error it might have.
You handled it well. Once or twice I felt that a higher price really wasn't justified. I may give it a go in a similar, well-explained manner, if the situation ever arises again. Definitely don't want to annoy the seller during negotiations. Thanks for the pointers.
Sounds like a really good find you have there.
Got one of these
http://www.bkprecision.com/products/power-supplies/1739-low-current-high-resolution-dc-power-supply-30-v-999-9-ma.html on ebay. Seller had it for "parts or not working", I took a chance and offered $88 (+$22 shipping). It looks and works like new, even the calibration is near perfect.
Not sure if I would pay the $500+ street price, but I like it. My only issues are that it powers up with the outputs on -- no good reason for that at all, and the 4mm jacks are just junk. Output is exceptionally clean, virtually no overshot, fast current limit kick-in, nicely designed course/fine controls and totally silent operation, there's no stink'n fan!!!
[Clarification: The 1739 boots up in the last (saved) state that you left it in. If you turn the output off, wait 3 seconds (the stated time to save changes) then power off the unit it will boot back up with the output off.]
So the output on/off switch on the B&K is a 'soft' key rather than a switch that mechanically latches, or something that sets a condition that the supply remembers when turned off and back on again? That seems like a poorly thought out design. (Seems you think the same.) I wonder what the thought process behind that decision was...
Otherwise, nice looking supply.
-Pat
I've been on a bit of the retro kick lately. Picked these two up in trade for an early 2000's Sony amp that had sat on the shelf for about 10 years. The Leader scope's power button was broken (at the switch itself, all the way in the back) and it was covered in solder splatter, both were quickly remedied and it looks/works great, just need to clean the knob contacts on Channel 2 and it'll be a flawless little 50Mhz 2 channel CRO.
The power supply works somehow, but there's a HUGE burn and the remains of a resistor on one channel and the remains of an exploded diode on the other. Had a close look and someone's jerry rigged it so that current limiting and voltage regulation work, but now the OC protection spikes it to negative voltages and the fine adjust knobs have some odd behavior. Luckily, the original manual was included and it has a nice legible schematic. Gonna restore the original circuitry and see how she does. Looks to be a re-badged Lodestar 303d, dual tracking 0-30v 3a.
Sorry about the pic... the iphone strikes again...
So the output on/off switch on the B&K is a 'soft' key rather than a switch that mechanically latches, or something that sets a condition that the supply remembers when turned off and back on again?
Exactly. It nicely says "OFF" on both displays when the output is off, but powers up with the output's on. If you hold in the ON/OFF button (briefly) while powering up it will startup in the OFF state. I was thinking about embedding a little processor inside that will do just that. If you hold in the ON/OFF for more than couple of seconds on power up it enters the calibration mode. This allows you to calibrate the supply using just the front panel controls. It also talks SCPI so that's another way to potentially solve this issue, by remotely controlling the ON/OFF setting.
Hi
I got depressed after the Brexit vote (and realised everthing is going to go up in price), so I did some retail therapy.
So far I have received
dual laser non contact thermometer (on the right)
Transistor tester (also tests other components, bought it to check ESR on caps)
I got depressed after the Brexit vote (and realised everthing is going to go up in price), so I did some retail therapy.
Really MosherIV, you needed an
excuse to buy some more gear???
I concur that it is excellent therapy though!
Got one of these
http://www.bkprecision.com/products/power-supplies/1739-low-current-high-resolution-dc-power-supply-30-v-999-9-ma.html
Output is exceptionally clean, virtually no overshot, fast current limit kick-in, nicely designed course/fine controls and totally silent operation, there's no stink'n fan!!!
Yeah, passively cooled linear supplies are the best. Since most of the gear in my lab is fanless, it makes the others seem really loud when I need to turn them on.
Regarding the output turning on by default, perhaps there's a setting to change that? Might even be only via SCPI.
If there is one, it's not documented. The documented SCPI commands for the BK 1739 are really limited, but all work as described in the manual.
OK, well that's a bummer. If you do embark on the microcontroller override project, I look forward to seeing more about it.
A few binding posts... I found in the back of a closet and I was bored...
I'm sure I'll get a little flack for it, but hey, it's a $5 power supply with 12v, 5v, and 3.3v rails and OC protection. I'm sure I'll find a used for it from time to time.
Why flak? Lots of people make use of ATX power supplies that way. Hey, you put some otherwise-dormant binding posts to good use as well.
Why flak?
Lol new to the board and well, to be honest it I've seen some amazing high spec kit on here so far!
Hi
Not sure how finding stuff lying around is in the spirit of the title of the thread but ok, if it makes you happy
Not giving you flak but some pros and cons:
Pros - atx psu cheap, various voltages, high current ouput
Cons - no current limiting, relativley noisey
And no programmable voltage. But for the price and modification effort, it is quite handy.
If you need more current, get a server psu, those are not really expensive, and can deliver tons of Amps.
Cons - no current limiting, relativley noisey
And usually regulated on a single rail, which got me to stop using that kind of PSU for projects...
Hi
Not sure how finding stuff lying around is in the spirit of the title of the thread but ok, if it makes you happy
lol, i bought the binding posts!
A few binding posts... I found in the back of a closet and I was bored...
I'm sure I'll get a little flack for it, but hey, it's a $5 power supply with 12v, 5v, and 3.3v rails and OC protection. I'm sure I'll find a used for it from time to time.
Don't knock it. It certainly looks a little better put together than this
An industrial equipment elapsed hours meter on a PSU is fairly unique I imagine.
Thanks to
julius oe. for that work of art!
Awesome. I wish I had photos of the "packaged in a cardboard box painted with a black marker" audio amp with VU-meters and "OMG high power" LEDs I built when I was a kid...
Mains PSU in the "perfectly insulated" cardboard box as well of course.
There's a topic about ugly repairs. I'll look for a topic about... so good looking... stuff.
I hope there is one.