HP 6236B Triple Output Power Supply (w/ talk about GPD-3303S)

[JenniferG]

Nice supplies those 6236B's. I did AoE 2nd edition with one in about 1996! Literally just bought it's successor yesterday, the E3630A as I regretted selling it years ago. If you want to get through AoE cheaply you can make do with one supply. I did when I did the old 2nd edition anyway. Had an 8xAA battery box and a croc clip lead as a second supply. If not the new HY1803D linear supplies are dirt cheap and aren't terrible.

Also skip the PB-503 breadboard. Spend the money on a nice sweeping function generator. HP 3312A is spot on for that course.

Incidentally I did the AoE course, then I did an EE degree and the AoE course was far more valuable.

Testing electrolytic capacitors... I'd just ignore this. They are almost certainly fine if the supply is operating correctly.

Wow thanks for all that useful info   Really cool to have people here willing to give a newb some advice to get me going in the right direction.  I am quite excited actually to start going with this.  I don't work so I have a lot of time on my hands and this would be as good a way to spend extra time.  My goal is to learn enough to where I can design cool and interesting things and make them a reality.  Also, want to save a lot of money building my own modular synth instead of the individual expensive modules.

Yeah I have no intentions of buying that bread board.  I bought a bunch of MB-102's for $2 from china.  I love this breadboard spring vise tool that breadboards sit in.  I printed it on my 3D printer.  It should do the job   [Cost me like $1 in plastic to print.. uses rubberbands to the wings are self-adjusting.. they really hold any pcb well!]

http://www.thingiverse.com/thing:957376





I also mount switches, knobs and what not on little perf board to make them breadboard friendly (a few examples in the above photo I snapped).

I'll have to look into that HP sweeping function generator.  Is it not something an iPad or PC SOund card could produce?  Too low of Freq range? i.e. 20k

[JenniferG]

Found one of those HP sweeping function generators for only $120 plus $24 shipping:

http://www.ebay.com/itm/HP-AGILENT-3312A-13-MHz-FUNCTION-GENERATOR-/162321403239

Missing a knob, allegedly works.

[SingedFingers]

Not a bad price. Paid more than that for mine but I'm in the UK and quality gear is far more expensive. The missing knob is actually a button cap to set the cal position for the offset so this is likely fine.

Here's what you get for your money:



Also it has AM and FM modulation and burst/pulse support which is useful for playing around with filters, PLLs and digital. The thing is a swiss army knife without having to spend on DDS kit.

Edit: regarding using a sound card, probably not. For a ton of labs you need a 50 ohm output impedance and a large voltage swing. That generator also hits 13MHz which is far higher than you can get out of a sound card. Sound cards are really useful though for audio and things like THD analysis so don't discard that idea

[bitseeker]

I've had one of these for over 25 years and other than replacing an electrolytic capacitor it just keeps on working.

I need to learn how to test an electrolytic cap.
...
I've tested one before but only with a capacitance meter checking the uF only.  I've learned recently that isn't enough and I need a $100 or so LCR meter.

Unless your power supply is misbehaving or showing a lot of noise on its outputs, you don't need to check the caps in it. However, it is good to have an ESR meter for troubleshooting. Bad capacitors are a very frequent cause of power supply problems in all kinds of devices.

You don't have to spend a lot of money, though, on a tester since a bad capacitor's ESR will be significantly higher than a good cap's. Grab yourself one of the ATmega-based ESR tester kits (tests more than just capacitors). They run $10-30 depending on the model and whether or not it comes assembled or with a case. Search for the "$20 transistor tester" thread. Plenty to read and the software/hardware is open-source.

If you like/prefer analog testers, search for the "5 transistor ESR tester" thread. It's a very simple circuit to build and works with an analog panel meter.

[K5HJ]

I had to replace C36 in the reference supply.  The symptom was low output voltage due to the reference being too low.
This can be verified simply by checking voltages, a capacitor meter is not really necessary. I got by for many years without one.

Randy

[JenniferG]

Just bought the Instek GPD-3303S as well (the version without overshoot problem).  $144 including shipping -- allegedly in great condition.. We'll see!  Anyways, I hope this was a smart move / value.

[JenniferG]

So I got this new HP power supply as you know:



But I have absolutely no leads for it.  What would be be the best way to get the power from this supply to an MB-102 breadboard strip?  As is, I'd just loosen the the terminal knobs, wrap a piece of 22 awg wire around it and tighten it, then just hook that wire directly into the board.  I am assuming there is a better way?

Just as I was clueless about probes & lead kits with my Fluke 8050A (got that cleared up thankfully), I am clueless about leads for HP power supplies.  Do these receive unprotected male banana plugs?  Is there a standard connector for most all test power supplies, as there is a standard for most DMM's? Do I want silicone coated leads instead of pvc? 

What would be the best brand to get? i.e. best value (affordable but good).  e.g. I am settling on Probemaster kit for $28 for my DMM.  Just need something similar for this test supply and whatever adapters I need to safely get the power to some MB-102s.

Thanks

[SingedFingers]

Use a breadboard with binding posts attached to it. I use one of these (and a couple of Wisher ones) which have a metal base and binding posts:



Then run 4mm <--> 4mm banana leads to it. Connect your instruments to the binding posts OR use minigrabbers to connect them in circuit. Don't try and connect everything up using bits of wire and binding posts. If you move anything it'll rip bits of your circuit out.

I'll post a picture later of my set up but I'm about to go on a conference call for 2 hours (fun).

[Cerebus]

Use a breadboard with binding posts attached to it. I use one of these (and a couple of Wisher ones) which have a metal base and binding posts:



Then run 4mm <--> 4mm banana leads to it. Connect your instruments to the binding posts OR use minigrabbers to connect them in circuit. Don't try and connect everything up using bits of wire and binding posts. If you move anything it'll rip bits of your circuit out.

I'll post a picture later of my set up but I'm about to go on a conference call for 2 hours (fun).

+1 on all of that.

Additionally a couple of tips to go with it.

Develop a personal colour code for dealing with multiple supplies and polarities and use it to choose what colour leads to connect your breadboard and PSU. Pick colours that match your breadboard's posts. If the binding posts on your board don't have the right colours or a restricted range of colours, cheap nail varnish is a good medium to use for re-coding them. That way if you physically disconnect your PSU to use for something else, you've a good chance of not mis-connecting it when you reconnect it to the breadboard. Where possible, keep the same physical order on PSU and breadboard binding posts.

Some time you are going to hook your PSU up the wrong way to your breadboard. Cue !BANG! and release of the magic smoke. A handy trick to minimize the damage you can do is to strap some reverse biased diodes between the binding posts on your breadboard. That way if you get it wrong you'll only apply 0.6V or so 'the wrong way around' to any components on that particular power rail and your PSU will harmlessly go into current limit. Pick big beefy diodes rated to handle the full load of your PSU for at least 60 seconds. A 3A 2W diode is going to be quite sufficient unless you're using a monster PSU. This doesn't protect you from all possible mistakes, but it does catch the commonest ones.

Note that if you use that last trick and you do end up mis-connecting your power cords it may take you some time to find the problem because the PSU and diodes will just quietly deal with the problem. However, I'd rather be scratching my head for 10 minutes than picking bits of exploded electrolytic cap out of my grizzled beard or, as happened to me last time I got this wrong, looking at the dead, smoking remains of £7 worth of  LM399 voltage reference.

[SingedFingers]

Excellent idea with the diodes. That mistake has as well cost me a few opamps, electrolytic caps and nearly an eye or two in the past

[JenniferG]

Thanks guys.  I suppose I should be wearing protective glasses anytime I build a circuit.

[SingedFingers]

I tend to wear them most of the time. Clipping leads is probably more dangerous based on probability.

[Cerebus]

Can't abide safety glasses if I can avoid them (which is not always).

A common trick is to have a sheet of clear acrylic handy, with some stand-offs in the corners or just a couple of bits of 4x1 timber screwed to the edges. Before you first power a breadboarded circuit on you just cover the whole thing with the sheet. It also stops you dropping tools into the middle of a layout, bending pins and sending components flying; which, of course, I have never *ahem* done.

[mmagin]

With properly-functioning sub-1 amp current limits on low voltage circuits, I've generally not had anything explode when I applied power.

The one reason I like having an adjustable current limit (as compared to the 6236B mentioned above) is that I can set it low enough to usually not even damage ICs if I connected things wrong.  But most parts are cheap, so it's not a big deal.

[mtdoc]

What would be be the best way to get the power from this supply to an MB-102 breadboard strip?

I agree with SingedFingers that a breadboard with binding posts is the best way to go. But for those times you aren't using one of those type of breadboards, good banana jack to minigrabber test leads work well. Just use a short length of 22 gauge solid core wire to connect between minigrabber and the breadboard power rails.

You can get high quality ones for a good price at Franky's eBay store here

[JenniferG]

Didn't know you could use the same test leads you'd use on a probe, on a power supply.

[bitseeker]

As long as they're 4mm banana plugs, they'll work. It's just wire. Just note that some jacks work with shrouded plugs and some don't. Having a couple of leads with retractable shrouds can be handy sometimes because they'll work in either kind of jacks.

If you have a university nearby, check Craigslist or similar. Students often sell off their lab kits when they're done with them. They may have banana leads, scope probes, BNC patch cables, passive components, ICs, etc. depending on the class.

As for current limiting, one could make a circuit as an add-on to the power supply's output, if needed.

[SingedFingers]

When I did university they supplied all our kit, which we promptly pilfered

[BU508A]

Didn't know you could use the same test leads you'd use on a probe, on a power supply.

Perhaps this is a stupid question, but do you have a solder station?
With this and some nice tools you can assemble some cables for your needs.
And sooner or later you need one anyway.

Examples for imho good soldering stations:
http://www.ebay.com/itm/JBC-HD-2B-Power-Lotstation-mit-Lotspitze-470-014-/222417228778 (soldering tip C470-014 recommended in your case, probably the C470-013 for finer soldering works)
http://www.ebay.com/itm/Hakko-FX951-66-FX-951-Digital-Soldering-Station-FH200-01-Variety-Tip-Bundle-/161807824599
http://www.ebay.com/itm/Weller-WESD51-Digital-Soldering-Station-with-Chisel-Tip-Bundle-Tip-Cleaner-/171943304353 (the soldering tips aren't the smallest but one can find them quite easily on ebay)

[JenniferG]

 Yes I have a cheap Velleman soldering station with a simple pot.   Right now I'm working on getting a proper one with temperature control In the sub $100 range -- analog not digital.

[JXL]

Use a breadboard with binding posts attached to it. I use one of these (and a couple of Wisher ones) which have a metal base and binding posts:



Then run 4mm <--> 4mm banana leads to it. Connect your instruments to the binding posts OR use minigrabbers to connect them in circuit. Don't try and connect everything up using bits of wire and binding posts. If you move anything it'll rip bits of your circuit out.

I'll post a picture later of my set up but I'm about to go on a conference call for 2 hours (fun).

+1 on all of that.

Additionally a couple of tips to go with it.

Develop a personal colour code for dealing with multiple supplies and polarities and use it to choose what colour leads to connect your breadboard and PSU. Pick colours that match your breadboard's posts. If the binding posts on your board don't have the right colours or a restricted range of colours, cheap nail varnish is a good medium to use for re-coding them. That way if you physically disconnect your PSU to use for something else, you've a good chance of not mis-connecting it when you reconnect it to the breadboard. Where possible, keep the same physical order on PSU and breadboard binding posts.

Some time you are going to hook your PSU up the wrong way to your breadboard. Cue !BANG! and release of the magic smoke. A handy trick to minimize the damage you can do is to strap some reverse biased diodes between the binding posts on your breadboard. That way if you get it wrong you'll only apply 0.6V or so 'the wrong way around' to any components on that particular power rail and your PSU will harmlessly go into current limit. Pick big beefy diodes rated to handle the full load of your PSU for at least 60 seconds. A 3A 2W diode is going to be quite sufficient unless you're using a monster PSU. This doesn't protect you from all possible mistakes, but it does catch the commonest ones.

Note that if you use that last trick and you do end up mis-connecting your power cords it may take you some time to find the problem because the PSU and diodes will just quietly deal with the problem. However, I'd rather be scratching my head for 10 minutes than picking bits of exploded electrolytic cap out of my grizzled beard or, as happened to me last time I got this wrong, looking at the dead, smoking remains of £7 worth of  LM399 voltage reference.

+1 on the binding posts/banana jacks.  You can't have too many of them.  I use heatshrink tubing to color-code my cables and the jacks on the breadboard & power supplies.

[Cubdriver]

Nice score on that HP supply. 

For interconnects, I like the stacking banana cables from Pomona Electronics.  This Digi Key link should get you to a page showing them:

http://www.digikey.com/products/en/test-and-measurement/test-leads-banana-meter-interface/627?k=Pomona&k=&pkeyword=Pomona&pv970=63&pv970=60&pv970=56&FV=fff40023%2Cfff80405%2Cffe00273%2C2dc0eae%2C33c0223%2Cb5800c7%2Cb5c00c7%2Ce0c000e&mnonly=0&newproducts=0&ColumnSort=0&page=1&quantity=0&ptm=0&fid=0&pageSize=25

They're not cheap, but are well made and will last.  Buy once, cry once.

-Pat

[JenniferG]

Nice score on that HP supply. 

For interconnects, I like the stacking banana cables from Pomona Electronics.  This Digi Key link should get you to a page showing them:

http://www.digikey.com/products/en/test-and-measurement/test-leads-banana-meter-interface/627?k=Pomona&k=&pkeyword=Pomona&pv970=63&pv970=60&pv970=56&FV=fff40023%2Cfff80405%2Cffe00273%2C2dc0eae%2C33c0223%2Cb5800c7%2Cb5c00c7%2Ce0c000e&mnonly=0&newproducts=0&ColumnSort=0&page=1&quantity=0&ptm=0&fid=0&pageSize=25

They're not cheap, but are well made and will last.  Buy once, cry once.

-Pat

I see four foot stackable  banana to banana Pomona cables for only $5.99 a piece on digikey. Am i not looking at the right ones?  Seems affordable.

[mtdoc]

Nice score on that HP supply. 

For interconnects, I like the stacking banana cables from Pomona Electronics.  This Digi Key link should get you to a page showing them:

http://www.digikey.com/products/en/test-and-measurement/test-leads-banana-meter-interface/627?k=Pomona&k=&pkeyword=Pomona&pv970=63&pv970=60&pv970=56&FV=fff40023%2Cfff80405%2Cffe00273%2C2dc0eae%2C33c0223%2Cb5800c7%2Cb5c00c7%2Ce0c000e&mnonly=0&newproducts=0&ColumnSort=0&page=1&quantity=0&ptm=0&fid=0&pageSize=25

They're not cheap, but are well made and will last.  Buy once, cry once.

-Pat

I see four foot stackable  banana to banana Pomona cables for only $5.99 a piece on digikey. Am i not looking at the right ones?  Seems affordable.

That's right.  The Pomona plugs are great but I'm not crazy about the PVC insulated wire used in their test leads. I prefer silicone.

You can get the Pomona plugs on digikey for $2 each then make your own test leads with 12 gauge silicone insulated wire from Franky on eBay or from HobbyKing.

[SingedFingers]

The PVC is quite rigid on them but at least they stay put unlike the flappy silicone ones which turn into a spaghetti nightmare.