First Build Tubescreamer

[ShOrEbReAk]

Hi all

Finally started my journey into pedal building with the tubescreamer PCB from tayda. I have some noob questions.

The parts list calls for a 50pf ceramic cap (the one item i missed on my order) and I stopped by jaycar to see if they had any. Well they do but in 48pf and 52pf no 50pf, I asked the salesman whether getting the 52 to cover it would work as a higher value and he couldn't tell me.
Can I substitute a film box type or use 2 ceramics which would make up the value? I am stumped.

As I said I am new and I searched in the forums but couldn't find anything to help. sorry if it has been brought up before but I am learning hahahah.

Troy

[PRR]

Welcome.

Nearly all audio caps can be +/-10%, even +/-20%, with hardly any audible difference.

A 50pF cap is likely in there to reduce super-sonics, and the exact value is un-important. 100pF *might* nick your upper overtones. 25pFd *might* make supersonic troubles (inaudible squealing and odd response) more likely.

[ShOrEbReAk]

PRR cheers for that!

I will try it and see what happens. I wasn't too sure if it was a power or signal designated cap.

Thanks again

Troy

[thermionix]

Not familiar with the Tayda version, but in the original tube screamers there is a 51pF cap in the clipping section, and I would guess that's where they're calling for a 50pF.  It's just a more common value, generally easier to find.  As Paul suggested, you won't hear any difference between 47, 48, 50, 51, or 52.

[ShOrEbReAk]

Thermionix

I had a 47pf so i used that and will see how i go. If its not that noticeable i may have dodged a bullet hahahaha. I really need to find out what certain parts of the circuits do so time will help with that I guess.

Cheers

Troy

[ShOrEbReAk]

Hi

I got the effect working only thing is I need to make a booster for after it as it is quieter than the clean signal hahahaha. The joys of building i guess, just means another pedal to build now hahahahah

I'm addicted now!

Troy

[bluebunny]

I'm addicted now!

That was quick!   

If your overdriven signal is quieter than when bypassed, then check carefully you've got all the right values in there.  There's plenty of gain in a tubescreamer; you don't need a booster.  Read this article at GeoFEX: it's very informative.

[deadastronaut]

+1 yep , theres something up with that....should be very loud..

[ShOrEbReAk]

hey

cheers for the information. I went back and started checking the values with the multi-meter and some are showing values others aren't. I am going to check my batches i bought from Tayda in case I bought duds. But if the effect is working albeit lower does that mean some resistors etc are duds?

Thanks

[Kipper4]

+1 yep , theres something up with that....should be very loud..

Here you go


http://www.diystompboxes.com/smfforum/index.php?topic=29816.0

[ShOrEbReAk]

cheers for the info.

I couldn't get 220 ohm 1/4w resistor so the guy said use a 1/2w as it had the same size legs, could this be it? otherwise I will sort it out tomorrow morning when my eyes are refreshed and the brain also to go over everything.  otherwise I have probably put the wrong value in somewhere in my messy haste to get building.

troy

[slashandburn]

A half watt resistor would be fine, nothing to worry about there.

If you can't see anything obvious get your multimeter and/or audio probe out.  Plenty more people who will help if you can post voltages and/or pictures. Oh and the schematic you used to build from. Otherwise we're all just guessing.

Since you suspect having picked up a wrong value resistor, and suggested the only thing wrong with it is the effect is quiet when engaged, I'll indulge myself and take a guess that the 1k resistor in series with the volume control you've put in a much higher value.   It's a stab in the dark though. 

[duck_arse]

ShOrEbReAk - if you have any parts questions, it is better if you ask here first, that way you can tell the clown helpful counterman at jaycar which way is up, and what you actually want. besides a mobile phone charger.

also, g'day.

[bluebunny]

It's unlikely you have any duds.  Sorry to say, but it's more likely to be pilot error.  But we all do that: join the club.    And you won't get meaningful resistor readings when everything's all soldered in.  Take Rich's advice and follow the debugging thread: it really does work.  And btw, I hope you didn't waste $2.45 on a 2134!  A 20c 4558 would be much more appropriate.    Those Tayda boys are a bit cheeky...

[ShOrEbReAk]

Hi all

Thank you for the responses. I am going to follow the debugging procedure and possibly build an audio probe today as well.

Slash- cheers for the info on using a 1/2w and I will check the 1k as you mentioned.

Duck- as a newbie I thought about asking those questions would annoy people as it has probably been asked before and the analogy of the salesman is spot on hahahaha all they really wanted was for me to buy a soldering iron and extra stuff. he knew where the parts were but not really how to use them. bit of the blind leading the blind.

BBunny- I did buy the 2.45 2134 from tayda but I also paid 8.35 for one from jaycar as i couldn't wait for the tayda delivery. I stocked up on parts before starting this journey on the recommendations from a guy on youtube and bought other op amps etc so i probably could have used those. Where can I get the 20c variety?

thanks again for all the help, I think I am going to enjoy this place.

Troy

[bluebunny]

I did buy the 2.45 2134 from tayda but I also paid 8.35 for one from jaycar

Ouch!

Where can I get the 20c variety?

The original TS had a 4558.  Costs pennies compared to the pointlessly-hifi 2134 (it's a distortion pedal, after all!).  Or try a TL072 - also way under a buck.

thanks again for all the help, I think I am going to enjoy this place.

You're welcome.  We're gonna enjoy having you along for the journey.  (And you can't get off, btw.  )

[thermionix]

besides a mobile phone charger.

Ah, I see Jaycar must be Australian for Radio Shack.  Do y'all still have Dick Smith's down there?  I still have a cheapie multimeter that I bought at one 20 years ago.  I seem to recall quite a few components for sale there, way more than Radio Shack had even back in the good ol' days.

[PRR]

> I couldn't get ...1/4w resistor so the guy said use a 1/2w as it had the same size legs

Might as well say it has the same number of legs.

ALL modern resistors have way-skinny legs, and are pretty sure to fit your holes.

If not, time to learn how to drill.

I'm having a party. I need to fetch 200 kG of beer. That's almost 1/4 ton. I go out in my driveway-- no 1/4 ton truck!! What to do?

Can I use the 1/2 ton truck?

Yes, of course, almost certainly. A 1/2 ton truck will carry a 1/4 ton load no sweat.

At least 99% of the time. Actually 1/4 ton trucks are rare in the US, but common in Japan. There, they are built less than 5 foot wide, to fit narrow alleys. My 1/2 ton truck is over 6 feet wide. If I have to get through a 5 foot gate at the beer store, I'm in trouble with the 1/2 ton, in-like-Flynn if I had a 1/4 ton.

That's the only "problem" with a 1/2W resistor where a 1/4W would be OK. If the layout is very tight, a 1/2W may not fit the available space. Most layouts are not so tight that you can't get it in there. Maybe crooked, but connected.

And price. When I was young, 1/2W was most common and thus the cheapest type. 1/4W and 1/8W parts were for hearing-aids and space-rockets and cost much more. Since then everything has got smaller. 1/4W is now the most popular and cheaper than 1/2W. The difference is never enough to bother a DIY budget.

[ShOrEbReAk]

Hey

Blue- Definitely along for the journey and stuck here gladly 🚷. Thanks for the heads up on the other options too.

Thermo- dick smith is here as an online retailer of electrical good such as tvs etc, I reckon they stopped the hobbyist parts in the early 90s. So we are stuck with jay car who do charge exorbitant prices but if you want something they are there and no waiting for mail orders.

In the haste for my daughters cricket this morning I went yet again to jaycar for my needs for the audio probe and forgot the capacitor for the probe. If I need the 600v I am stuck till tomorrow hahahahaha. I have a solid state amp and if we are only talking 9v not the 500v of an amp is there an equivalent smaller cap I can use? Also this is a sneak in away from topic question I bought some vero board and want to know if you just use the legs of components for the bridging or is there some solid wire I need to make the joins/ paths. Hopefully it doesn't cost extra for other questions or I might have to start a beer tab on the bar hahahahaha

Second question is I bought some cable to make a cable for sound from my speakers as I don't have a tone generator. Will this work? And do I need to earth this as well. I am hoping the probe attaches to ground and the cap will test and the signal cable will go to in on the effect and ground with the other cable? Hopefully you get my drift.

PRR you boys over there have some BIG trucks for daily drivers hahahah

Cheers troy

[ShOrEbReAk]

WOHOOOOOO

I had 2 incorrect film cap values. It is a lot louder now even comparable to the non pedal sound but with crunch!

I didn't get the probe built but its on the to do list! I still need to know the capacitor value as in my last post and the audio input idea.

Thankyou again to all that helped with ideas and suggestions and I will post some pics of the finished product and some usual gut shots.

Troy