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Noisy Cricket problems!

Started by dan6896, February 02, 2011, 12:01:20 AM

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Dimi Pana

#30
Hey, how about this:

Looking in the NC schematic (RadioShack build or PCB build):

VR2 is the Gain pot, rated for 1KΩ

VR3 is the Tone pot, rated for 100KΩ

However...

Looking at the parts list (in both builds) it appears that these values have been inadvertently reversed:

Gain is still VR2 but rated at 100KΩ

and

Tone is still VR3 but rated at 1KΩ.

--

So which is correct? The Schematic or the Parts List?

(Pls, see attached!)

phatt

I'd just go with a 10 K pot as 1k seems a bit silly.
Phil.

J M Fahey

QuoteGain is still VR2 but rated at 100KΩ
No, look again, in the layout just above the parts list, VR2 *now* is Tone.
Its *value* and *function* match the schematic, its *designation* (VR2) does not.

QuoteTone is still VR3 but rated at 1KΩ.
Same as above, VR3 now is gain and still 1K.

So in a nutshell: schematic and layout both work, but their "labels" (for lack of a better word) do not match.

*BIG* famous companies have errors greater than these (sometimes even on purpose), so I am eager to forgive Beavis Audio which very probably is a one man operation.
Nothing against that, of course !! ;)

Which version are you building?
Didn´t check the PCB transfer one, but it probably works.
The Radio Shack version looks very confusing even for me, much more so for a beginner, because they use a PCB which was designed with a very different use in mind, I find it very easy to make wiring mistakes with it.
I think I will design and post a perfboard (which is really universal) version of the Smokey amp, which as you already heard sounds impressive, has no pots, and about 5 or 6 parts total.
Check here tomorrow.

Dimi Pana

#33
ΟΚ, this is probably a waste of time for you all, it was a good exercise for me.

Here's what's going on:

There are two build versions posted by BeavisAudio. One is a PCB based one the other is the RadioShack (RS) version. BTW, I am building the RS version since at this point I do not have what it takes (knowledge and tools wise) so I cannot print and etch my own PCB.

Each version includes (at least) the following:

1. Parts List

2. Schematic

3. Parts Layout


Here's what the error is (regarding the V, G and T pots):


In the PCB version:

The "Parts List" agrees with the "Schematic" and both disagree with the "Parts Layout"


In the RS version:

The "Schematic" agrees with the "Parts Layout" and both disagree with the "Parts List".

---

Of course, all this is immediately recognizable by all you experienced people, unfortunately in my case it is a "show stopper" since I realize the discrepancy but I am unable to distinguish between RIGHT and WRONG.


---

However, by reading your posts and doing some research myself, here's what I will do:

VR1 = Volume = 10KΩ

VR2 = Gain = 1KΩ (*)

VR3 = Tone 100Ω

---

Νow, because, RS do not carry a 1KΩ pot, and since phatt(*) already suggested to change it with a 10KΩ,  is it OK to use -instead- a 5KΩ ( just happen to have one)  so I do not have to buy it? I do not want an explanation why (to save you time) just a YES or a NO.  ;)

---

Last question for today: This design calls for a 100nF "poly film" capacitor at C3. JMF suggested I change it to a 10μF (right?). I cannot find this value in film but I can in electrolytic. Can I substitute film with electro? Again, I am asking for a YES or NO answer, obviously I'm interested in the WHY, please answer only if you have a short and simple one, anything longer just post a link on the net, let me then do the reading.  :tu:

---

How am I ever going to pay you all back for your patience, kindness and your hard-acquired knowledge offered for free? My family owns a small "Bed & Breakfast" motel in the Greek island of Santorini, so if you ever visit my country, please drop me a line, I might (actually for sure) be able to work something out for you. But please hurry, given the current financial instability and judging by the (poor) quality of the Greek politicians, I am not sure if in the near future Greece will still belong to the Greek people or owned by some big, inconspicuous financial conglomerate.  :'(   

J M Fahey

QuoteΟΚ, this is probably a waste of time for you all, it was a good exercise for me.
Friend, don´t worry about that, it´s not a waste of time and we take it as going to the Gym (another Greek word, of course) and working out our minds.
QuoteThere are two build versions
QuoteΝow, because, RS do not carry a 1KΩ pot, and since phatt(*) already suggested to change it with a 10KΩ,  is it OK to use -instead- a 5KΩ ( just happen to have one)  so I do not have to buy it?
Yes. It will not be as "smooth", as the big gain change will be cramped towards one end, but it will work.
QuoteLast question for today: This design calls for a 100nF "poly film" capacitor at C3. JMF suggested I change it to a 10μF (right?). I cannot find this value in film but I can in electrolytic. Can I substitute film with electro?
Sorry for not being clear, my mistake.
The original 10uF was an electrolytic; when Beavis changed that into 100nF, we are in ceramic/polyester, etc. area, not electrolytics, so he changed the spec.

QuoteHow am I ever going to pay you all back for your patience, kindness and your hard-acquired knowledge offered for free? My family owns a small "Bed & Breakfast" motel in the Greek island of Santorini, so if you ever visit my country, please drop me a line, I might (actually for sure) be able to work something out for you.
WOW !!!!!!!!! SANTORINI !!!!!!! One of the paces I HAVE to know in my life !!!
The (real, historical) origin of what we know as Atlantis, the Universal Deluge, amd many of Bible´s catastrophes.
Just hold a loose reserve for a room , ***someday**** I´ll be there.
WOWWWWWWWWWWWW !!! SANTORINI !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
QuoteBut please hurry, given the current financial instability and judging by the (poor) quality of the Greek politicians, I am not sure if in the near future Greece will still belong to the Greek people or owned by some big, inconspicuous financial conglomerate.  :'(
Don´t worry, Greece will survive, as it has for the last 2500 years.
And your politicians are MUCH BETTER than ours (ours meaning the rest of the World)
They are asking People to VOTE about their economic future and how their money will be spent.
Unbelievable !!
Except, of course, in the land that INVENTED Democracy 2500 years ago.
Not to mention Science, Art, Psychology, Logic, Geometry, Ethics, and 10000 other things, as we know them.

PS: for those curious about it, Santorini *was* a round island, which housed a very advanced (Minoan) civilization.
In 1600 BC, it showed its true face: it was a volcano which exploded with the power of a few atomic bombs
This picture shows a satellite image.
The land you see is what remains of the volcano, all that water in the middle is filling the explosion´s crater.
Imagine the explosion.

The Tsunami it created flooded coast areas up to a lot of inside land, from Spain to Egypt, Israel, Iraq, (Greece of course) and most of the ancient world known to us.
We have 3 versions of that historical terrible, remembered with awe for ages, fact.
Of course, each of them tells his own version, and thinks it only happened to them as punishment for something. (Very reasonable assumption considering nobody knew lands beyond a few hundred miles from their own)
1) Noah . Israel. <-- this one we know.
2) Deucalion (Greek) "Zeus loosed a deluge, so that the rivers ran in torrents and the sea flooded the coastal plain, engulfed the foothills with spray, and washed everything clean. "
3) Gilgamesh (Sumerian/Babylonic/Iraq)
   "1. Early in the morning at dawn a black cloud arose from the horizon.
...
   4. The thunder god Adad rumbled in the cloud
......
   7. There was stunned shock at Adad's deeds which turned everything to blackness. The land was shattered like a pot.
   8. All day long the south wind blew rapidly and the water overwhelmed the people like an attack.
   9. No one could see his fellows. They could not recognize each other in the torrent.
  ..........
  14. The flood and wind lasted six days and seven nights, flattening the land.
  ....................
   2. The terrain was as flat as a roof top.

As we can see, all three are telling the same story, in their own words.
All three lived around 1500/1600 BC.
The Santorini explosion happened (measured by scientific expeditions, including a National Geographic team) between 1400 and 1600 BC.
It was 4 times as powerful as that of Krakatoa (around 1880) which was seen all over Asia, the volcanic ashes reached Europe and America.