Build Shit - DIY - What's On Your Bench?

[WhiteWarlock]

sort of figured it out yet will need substituting 3904 for bc547 transistor and mutate some circuitry...

[WhiteWarlock]

currently out of BC547s...

BC547:
Features / technical specifications:

Package Type: TO-92
Transistor Type: NPN
Max Collector Current(IC): 100mA
Max Collector-Emitter Voltage (VCE): 45V
Max Collector-Base Voltage (VCB): 50V
Max Emitter-Base Voltage (VEBO): 6V
Max Collector Dissipation (Pc): 500 miliWatt
Max Transition Frequency (fT): 300 MHz
Minimum & Maximum DC Current Gain (hFE): 110 xe2x80x93 800
Max Storage & Operating temperature Should Be: -65 to +150 Centigrade

2n3904:
Features / technical specifications:

Package Type: TO-92
Transistor Type: NPN
Max Collector Current(IC): 200mA
Max Collector-Emitter Voltage (VCE): 40V
Max Collector-Base Voltage (VCB): 60V
Max Emitter-Base Voltage (VEBO): 6V
Max Collector Dissipation (Pc): 625 miliWatt
Max Transition Frequency (fT): 300 MHz
Minimum & Maximum DC Current Gain (hFE): 40 xe2x80x93 300
Max Storage & Operating temperature Should Be: -55 to +150 Centigrade


let's see what happens soon with some experiments/designs...
making new modules since CD40106s arrived... prototyping for pedal concepts...
hfe is way better in BC547.... ~shrug~

[crochambeau]

I almost use 2N3904 exclusively, but I also do a lot of cascading stages, so lower hFE is preferable (I've got a 5K lot of ONsemis and every transistor I've tested in it has measured 217). Honestly, if I could source a reliably consistent part in the 50 hFE range in a TO92 package I'd be happy.

I guess I'm not doing a lot of nV or super low mV input support though..

On my bench is an outboard reverb I built a while back and then sold to a friend to fund a tool purchase.

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I had originally built this for myself, and so took liberties with the build that I would not intentionally inflict on another. A while back the reverb send cable (external plug-in job unoriginal to the build) broke internally and provided an open circuit for the output transformer to work into. This cooked the output transformer, and while it was in for service I took it upon myself to correct the power supply situation I had cobbled together a few years before (essentially this was using two transformers in place of one). Unfortunately, the power transformer I had on hand provided more voltage that advisable to the rest of circuit, and so I inserted excessive series resistance to pull the voltage down.

This resulted in a somewhat starved plate condition that has changed the performance in a way that the owner of the unit does not prefer, so it's in again for some non-invasive B+ padding. I'm going to try some inductive solutions first, since I do not have an ideal PT on hand.

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I might also just punch a hole for a rectifier tube if that seems simplest.

[Indeterminacy]

On my bench is an outboard reverb I built a while back

What iron did you use for the choke and output?

[crochambeau]

On my bench is an outboard reverb I built a while back

What iron did you use for the choke and output?

Junk box iron, naturally. I think the output is a single ended 6BQ5 pulled from a console stereo, pretty sure it was something my uncle harvested originally. The choke either came along the same channel, or was salvaged while dumpster diving the electronics surplus store death (RIP).

I'm incredibly privileged to have had access to those channels, so much the better since I resist parting stuff out unless it's so far gone. ...but the downside is that I can't simply point to a new production part and say "I recommend using THIS!" to anyone wanting to roll their own.

Also on my bench is a Fostex R8 which likes to throw the drive belt pulley whenever I transition a reel out of a high speed transport mode. I've taken the fucking thing apart several times now (entire face has to come off to access the belt), and since superglue on the spindle didn't work I'm going to gently score or deform it to insure a press fit plus glue solution will stick.

[FAP]

Waiting on parts for a circuit bending project, so in lieu of getting to work on the main unit, I completed a peripheral to it: a photoresistor wired to a 1/8xe2x80x9d cable. Ixe2x80x99m going to put a 1/8xe2x80x9d switched jack on the main unit so that the cable can be plugged in or out at a whim to potentially be used for other projects.

[timdrage]

Nicely done have done similar myself, it's much neater and more playable than trying to mount an LDR on the device and having to have a switch for it

Today improved my Doepfer Wasp self-oscillation mod by swapping the advised 10k resistor for a 20k pot and tweaking it (and the on-board trimmer pots) till I got a more reliable range - previously it would peter out if you went too high or low.



More info on my mod herE: https://hackaday.io/page/6995-tweaking- ... lation-mod

Yesterday built the simplest part of the Ciat Lonbard Rollz-5 paper circuits. It does,,,, something. thinking

[FAP]

Nicely done have done similar myself, it's much neater and more playable than trying to mount an LDR on the device and having to have a switch for it

Who do you think I got the idea from?

[FAP]

Finally got around to putting LEDs on my springboard. To recap: the springboard is a roughly 5ft. long, 5in. wide piece of metal with all sorts of noisemakers on it. There's a contact mic at each end as well as a foot switch for that toggles between the mic(s) and a true bypass, meaning one could run an FX chain or whatever through the input of one/both sides, then switch to the physical sounds of the springboard by tapping the footswitch. I've included an updated, shoddily cobbled together panorama of it as it exists today; I posted an older picture of it in another thread before, but that was very early in the building process.

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[Indeterminacy]

my springboard

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