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TO-3 SYMASYM

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Rudi_Ratlos

Rudi_Ratlos

Member
Joined 2009
Joshvi, MJ777,

so we are at 6 PCBs.
Maybe some other DIY'ers show interest: I will open a new round of group-buy then.

Andrew: I offered versions for both TO3- (for example: MJ21195 / MJ21196) and TO264-transistors (for example: NJW0281 / NJW0302)
in this group-buy.

The reasons for my TO3 - offer have been:

- I layouted the TO3 - PCB version on behalf of a request of my DIY-friend Joe (see post #1)
- the thermal characteristics of TO3 - transistors are "unbeatable"
- I myself like the warm and tender "Phillysound" that the TO3s are able to produce

If it will come to a new round of group-buy, I will offer the TO264 - version (I have it as well).

Find attached a picture of the TO264 - SYMASYM ...

An externally hosted image should be here but it was not working when we last tested it.


... and let me give you my sound impressions of it:

I have built several DIY - AMPs so far: AMPs designed by Carlos, by Ron and by Mihai, ...

For example: this is my FC-100 - build:

fc-100e1xuz.jpg


... and even this one has to compete very hard with the SYMASYM that I layouted.

The SYMASYM is: easy-going, fast, very black bass and smooth trebles, you can tweak it, if you want, it does not need any exotic components,
it is never-tiring, it is the "work-horse" in my home, ..., it is the most beautiful, low cost AMP that I have ever come across.

Best regards - Rudi_Ratlos
 
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Rudi_Ratlos

Rudi_Ratlos

Member
Joined 2009
So: we are at 10 PCBs.
I just quoted the price. It is 12€ per PCB.

Shipment is worldwide and will cost 3.45€.

I will wait another week for further particpants and will give you payment and delivery details then.

Andrew: the use of the following transistorshas been tested and been approved:

- MJL3281A/MJL1302A
- MJL4281A/MJL4302A
- MJW0281A/MJW0302A
- MJL0281A/MJL0302A
- NJW0281G/NJW0302G
- MJL21194/MJL21193 (with min. fT of 4 Mhz !)
- MJL21196/MJL21195 (with min. fT of 4 Mhz !)

The use of Toshiba SC5200/SA1943 may result in changing the value of the feedback capacitor (see Pavel's review: symasym)

Best regards - Rudi_Ratlos
 

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Rudi_Ratlos

Rudi_Ratlos

Member
Joined 2009
Andrew,

I compared the datasheets of the MJL21196 (case: TO–3PBL) and MJ21196 (case: TO-3). The datasheets look almost identical.
Moreover I have sold more than 100 TO-3 SYMASYM PCBs and did not yet receive any complaint about a malfunction, ...

Pavel reduced the value of the feedback capacitor to 3pF in order or prevent oscillations, in case the mentioned Toshiba transistors are used.

Best regards - Rudi

P.S. The currently offered SYMASYM will feature TO-264 / TO-3P case transistors.
 
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