Search found 25 matches

by MerlynMetal
31 Aug 2020, 10:09
Forum: Parts Sourcing & Trading
Topic: Is this a 741 opamp?
Replies: 2
Views: 427

Is this a 741 opamp?

Hi,

I got these recently from a friend. He said these were DIP14 741 opamps. Somewhat unusual but according to datasheets not impossible. Is this so and which company manufactured them (I can't read that logo)?


741P DIP14
741P DIP14
by MerlynMetal
25 May 2015, 22:48
Forum: Modern Stompbox Effects (1975 - ...)
Topic: Boss - CE-3 Chorus Ensemble [schematic]
Replies: 41
Views: 33216

Re: Boss - CE-3 Chorus Ensemble [schematic]

In case the links are not working.
CE3comp.gif
CE3solder.gif
by MerlynMetal
16 Feb 2013, 13:49
Forum: Modern Stompbox Effects (1975 - ...)
Topic: Hughes & Kettner - Red Box mark II [schematic]
Replies: 14
Views: 6881

Re: H & K - Red Box ( H&K ) [schematic]

Transfer ratio 1:1
Primary winding:
Inductance 3,23 Henrys
DC-resistance 50 Ohms
Secondary winding:
Inductance 3,23 Henrys
DC-resistance 62 Ohms
According to this data Xicon part number 42TM016 which is readily available looks like an exact replacement. 42TM009 is also very close.
by MerlynMetal
12 Aug 2012, 20:15
Forum: Modern Stompbox Effects (1975 - ...)
Topic: AMT Electronics - S1 Legend series [schematic]
Replies: 633
Views: 241881

Re: AMT S1 Legend series [gut shots] [schematic]

The impulse sounds much better.
by MerlynMetal
09 Jul 2012, 20:31
Forum: Modern Stompbox Effects (1975 - ...)
Topic: AMT Electronics - S1 Legend series [schematic]
Replies: 633
Views: 241881

Re: AMT S1 Legend series [gut shots] [schematic]

2SK208-R's can be found easily but not in the US. The chinese ebay seller who has the 2SK208-Y can provide 2SK208-R as well but he wants more for them - 25USD for 30 pcs. Otherwise many online parts shops have the 2SK208-R but in bulk quantities. He also can get the MMBF5458 but it's even more expe...
by MerlynMetal
07 Jul 2012, 07:33
Forum: Modern Stompbox Effects (1975 - ...)
Topic: AMT Electronics - S1 Legend series [schematic]
Replies: 633
Views: 241881

Re: AMT S1 Legend series [gut shots] [schematic]

I agree the basic layout looks the same. It looks like there are several different markings for the same part.
by MerlynMetal
06 Jul 2012, 20:29
Forum: Modern Stompbox Effects (1975 - ...)
Topic: AMT Electronics - S1 Legend series [schematic]
Replies: 633
Views: 241881

Re: AMT S1 Legend series [gut shots] [schematic]

From All board photos that I have...
These pics are from 2009. Obviously they changed the PCB design and some parts since then.
by MerlynMetal
06 Jul 2012, 08:29
Forum: Modern Stompbox Effects (1975 - ...)
Topic: AMT Electronics - S1 Legend series [schematic]
Replies: 633
Views: 241881

Re: AMT S1 Legend series [gut shots] [schematic]

It looks like the marking 5C has nothing to do with any BATs.
by MerlynMetal
05 Jul 2012, 09:00
Forum: Modern Stompbox Effects (1975 - ...)
Topic: MXR - Zakk Wylde ( ZW-44 )
Replies: 41
Views: 37175

Re: MXR - Zakk Wylde ( ZW-44 )

...which to me are basically unusable.
All TS derivatives are useless by themselves unless used to drive the front end of a real amp or boost other pedals.
I haven't heard of anybody using only a TS derivative connected directly to a power amp.
by MerlynMetal
04 Jul 2012, 21:08
Forum: Modern Stompbox Effects (1975 - ...)
Topic: MXR - Zakk Wylde ( ZW-44 )
Replies: 41
Views: 37175

Re: MXR - Zakk Wylde ( ZW-44 )

I lost interest in this pedal but if I decide to "reopen" this project I'll do an SMD copy.
by MerlynMetal
20 Jun 2012, 14:58
Forum: Modern Stompbox Effects (1975 - ...)
Topic: AMT Electronics - S1 Legend series [schematic]
Replies: 633
Views: 241881

Re: AMT S1 Legend series [gut shots] [schematic]

please verify r39 value for me
I'm sorry, I meant tracing from original S1 board pictures posted here.
by MerlynMetal
20 Jun 2012, 13:39
Forum: Modern Stompbox Effects (1975 - ...)
Topic: AMT Electronics - S1 Legend series [schematic]
Replies: 633
Views: 241881

Re: AMT S1 Legend series [gut shots] [schematic]

I did some tracing from the original S1 board which indicates some minor changes in the power supply line:
S1 legend with cab-sim1.jpg
AMT S1 SMD bottom final.GIF
by MerlynMetal
15 Jun 2012, 10:20
Forum: Modern Stompbox Effects (1975 - ...)
Topic: AMT Electronics - S1 Legend series [schematic]
Replies: 633
Views: 241881

Re: AMT S1 Legend series [gut shots] [schematic]

I made a mistake, the diode isn't there, but the FET is 6AS.Mine is V.2A.The first fet doesn't need to be hi gain, 2N5458 is used in other versions, cause of the high VGS,so it doesn't clip the signal.Do you have more of these pedals? I hve some 2SK208 (JR) versions on the way, I bought some JY ver...
by MerlynMetal
03 Jun 2012, 21:44
Forum: Modern Stompbox Effects (1975 - ...)
Topic: AMT Electronics - S1 Legend series [schematic]
Replies: 633
Views: 241881

Re: AMT S1 Legend series [gut shots] [schematic]

So, if we use their component numbering as printed on their boards rather than letting the CAD application auto number then we can better compare differences between the components on a single board over 3 or 4 different pedals. Make sense?
Makes perfect sense. I was going to ask for that as well.
by MerlynMetal
27 May 2012, 14:49
Forum: Modern Stompbox Effects (1975 - ...)
Topic: AMT Electronics - S1 Legend series [schematic]
Replies: 633
Views: 241881

Re: AMT S1 Legend series [gut shots] [schematic]

If you follow the +9V trace on the pics you'll notice that it goes from (+) terminal directly to R49 and R48 BUT on the top side you can see that then it continues from C26 (+) terminal which is AFTER R49 to C9. Then if you follow the trace further you'll see that R12 (R112 on the schematic) is plac...
by MerlynMetal
26 May 2012, 20:45
Forum: Modern Stompbox Effects (1975 - ...)
Topic: AMT Electronics - S1 Legend series [schematic]
Replies: 633
Views: 241881

Re: AMT S1 Legend series [gut shots] [schematic]

Sorry I have no schematics but if you trace signal from input you'll see the difference.
by MerlynMetal
26 May 2012, 15:18
Forum: Modern Stompbox Effects (1975 - ...)
Topic: AMT Electronics - S1 Legend series [schematic]
Replies: 633
Views: 241881

Re: AMT S1 Legend series [gut shots] [schematic]

Below are pics of top, bottom and both layers. I wanted to attach the Sprint Layout file but the forum software doesn't allow it. Things to be done: 1/ There are some unallocated capacitors numbers that are not seen on Ice-9's pics. 2/ Couple of traces around the footswitch. 3/ VT10, 11 and 12 which...
by MerlynMetal
26 May 2012, 13:20
Forum: Modern Stompbox Effects (1975 - ...)
Topic: AMT Electronics - S1 Legend series [schematic]
Replies: 633
Views: 241881

Re: AMT S1 Legend series [gut shots] [schematic]

I'll do that and I'll need some help with couple of traces not well visible on pics. Also the bypass diode switching part is somewhat unclear.
by MerlynMetal
26 May 2012, 11:05
Forum: Modern Stompbox Effects (1975 - ...)
Topic: AMT Electronics - S1 Legend series [schematic]
Replies: 633
Views: 241881

Re: AMT S1 Legend series [gut shots] [schematic]

Hi,

Thanks to Ice-9' pics I'm almost done with the original double layer SMD PCB drawing for S1.
Is anyone interested in a factory made PCBs for S1 (or B1, P1) to share the expenses?