themadhippy

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If someone spills a bear over proprietary hardware you are

Ok apart from possible bryson how many of us have  included  bears in the venue as part of our risk assessments

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tripping on power up.

Sounds like in rush current,power your rig up in stages instead of all at once if possible

Diluted white vinegar has done the job for me  many  times,dont try pushing it through with a syringe,use the machine to heat it   and pump it through, and best do it outside.

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Well I am saddened that the worlds largest and only super store of used kit has not struck the Blue room members yet.

Ebay? im sure we've all heard of them   or do you mean usedlighting dot com?

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. As per your suggestion a missing fuse in an extension lead (so should fail on continuity) was a common one.

but continuity apart from the earth aint  required,what it will fail on is the polarity test

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I'd sometimes wondered about leaving "traps" for testers, like plugs with the fuses removed, so that they should be impossible to test properly without replacement. 

and then you start getting into the grey areas of how the regs are interpreted,does a visual inspection,which is to check for damage cover the fuse?what about opening the plug top isnt that disassemble,and good luck when the find your 600w drill   is fitted with a 13A fuse but is wired with 1.5mm hof5

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extruded

use that as a search term on cpc and it should give you 1 or 2 options,you can then narrow it down with the dimension  options.Ive used sevral of there hammond boxes and they look  ok,better than my  usual dicast box sprayed black

is sketchup warehouse still a thing,used to loads of usefull models on there,and its fairly painless,or used to be to convert to stl.

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rather than leap into trying to design my own (which may well be past my ageing brainpower these days

Take a look at onshape,the interface looks daunting at first,but soon found it fairly painless  with the help of a few youtube videos .

double check the pin out of the pot,the  ones ive got,the middle pin isn't the wiper as youd expect.,its  the bottom pin.

I've use several voltcraft 230rn, on various projects ,a few quid more than the ebay cheapys,but the measurement inputs are separate to the supply (9v) plus  you can configure them to show additional characters including  V A m u, set were the decimal point is. With a bit of clever switching they can be used for both voltage and current measurement with the appropriate  unit also displayed.You can find  the datasheet at  https://static.rapidonline.com/pdf/126564_an_ml_01.pdf

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, is there an alternative nice solution? 

Have someone like 5 star,  flight case warehouse etc build a custom case

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or my sums are wrong

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A Darlington will be at least 1.2V

there me first mistake, guess who just  thought, silicon tranny yea that'll be 0.6v then.

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It doesn't work relyably with the 4.7K but does with a 1K2 and draws just under a 1mA on that leg

Either the gain of the tranny is lower than the datasheet claims or my sums are wrong,but  either way you got it working

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You might want to build a darlington pair with your TIP120 's to give you more current gain from your sensor to the motor.

wouldn't that be a darlington quad as the tip120 is already a darlington pair

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I'm driving the base directly with the PIR O/P and it seems to work well.

you might want to add a resistor from the sensor to the base to limit the base current to help avoid the magic smoke appearing.

something like this should work

Any use https://www.etcconnect.com/CueSystem/

instead of a battery theres not a bloody big value cap hidden somewhere?

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Panel mounting 10 turn pots can be expensive to buy

wouldn't class £3.83 expensive,especially as you can pay that  for a bog standard dual pot

The problem I have with course/fine is the constant juggling act needed to get things just were you want them course down a bit fine up a bit course down a smidge,oops to far.

Another thought,if you've the space is to add in a dual fixed supply,its the most used part of my power supply set up,no pots to mess with,just a switch to swap between voltages.

31 minutes ago, partyanimallighting said:

Is this type of pot readily available online?

if you mean multiturn then yea,useless me posting links as they'll be uk centric,but a search for

3590S Precision Wirewound Potentiometer

should get you close

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Is it that this particular pot does not have a stop but continuous rotation

no ,they have stops, but it takes 10  rotations of the knob for full travel

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linear taper pots and I'm thinking that's what I'm looking for

yep that be the type

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and the 50K pot

personal choice,but I'd recommend a multiturn pot,you'll swear at it when you need to go to from the extremes of the range,but swear by it when your trying to dial in  an exact voltage.

might want to include an ammeter ,not essential but useful to see if that burning smell is the circuit under test or just your soldering iron being in the wrong place

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My first S-L was based around a free PCB given away in one of the electronics mags.

too complicated,mine was a torch lamp wired to the output of my first ever record player.

Personally id start from scratch as  my experience  of  cobbling  together different bits  from different manufacturers is  the magic smoke soon makes an appearance.Id go with couple of  op amps to do the beat detection feeding a counter to allow you to set the number of beats before reversal  and a bit of simple logic into an H bridge to drive your 12V motor

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If that's the case how could you ever control more than 32 devices with one board

when DMX was invented 32 units was considered big,I mean 186 dimmer channels wow,most of the    wiggly stuff either came with its own top secret protocol and desks,or was so expensive that  if you could afford 32 units the cost of a second operator and board was peanuts