RoHS gone MAD

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Hi to all,

I have a near new, Fender " Deluxe Reverb-Amp " on the bench.

This is a so called " Reissue " of a 22watt, all valve guitar amp first sold
back in 1965.

The circuitry is identical to the original except for one low cost component
that has been substituted  ....  like Vince Sorrenti famously says:  I see
it, but I doooaann believe it  !!!!

Inside the amp's chassis has been fitted an SMD board, about 50mm x 100 mm,
that does just *one* job -   it replaces the usual CdS photo cell in the
tremolo circuit  !!!!!

On the back of the SMD board, in copper, it says " ROHS  TREMOLO ".

The 12AX7 valve responsible for the tremolo effect is still fitted and fully
wired  -  but the connections that usually go to the Ne2 lamp and the CdS
cell are now routed the SMD board instead.

The main IC on the SMD board is an LM13700 transconductance amp -  plus a
TL072 and numerous transistors, caps etc. It does the job of mimicking the
CdS characteristic rather well.

But WHY  ??

How much EVIL cadmium is inside one, tiny CdS cell  ??

Remember: NiCd batteries are still being sold and still fitted to many power
tools -  even in Europe.

How completely bonkers  !!!!



....  Phil




Re: RoHS gone MAD


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Batteries are exempt from ROHS though.

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You're not wrong.
ROHS is all about "reduction", not total elimination, strange that a single
CdS photocell would put you over.
Interestingly, Digikey actually sell some CdS photocells that are "ROHS
compliant by exemption", whatever that exemption means.

Perhaps the CdS cell wasn't replaced because of ROHS?, it might just have
been a discontinued part which they could not find a suitable alternative?
The board is ROHS compliant, because, well, that's what they all are these
days as standard.

I'm surprised marketing didn't get a hold of the "solid state" update...

Dave.

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Re: RoHS gone MAD

"David L. Jones"


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** Shame about the " Battery Directive ".

http://en.wikipedia.org/wiki/Battery_Directive

Note how NiCds are still allowed in power tools.



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** The RoHS cadmium ban applies to the percentage ( max 0.01%) of cadmium in
any identifiable material or coating.

"  The maximum permitted concentrations are 0.1% or 1000 ppm (except for
cadmium, which is limited to 0.01% or 100 ppm) by weight of homogeneous
material. This means that the limits do not apply to the weight of the
finished product, or even to a component, but to any single substance that
could (theoretically) be separated mechanically-for example, the sheath on a
cable or the tinning on a component lead.  "

http://en.wikipedia.org/wiki/Restriction_of_Hazardous_Substances_Directive#Details


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** There is a general exemption for CdS photo cells used in professional
audio equipment (obtained by request from Marshall Amplification of the
K)  - it expires end of this year -  subject to review no doubt.

http://www.rohs.gov.uk/Docs/Exemptions%20without%20link%20backs/RoHS%20Exemptions%20-%20Cadmium%20 (2).pdf

Makes what Fender have done impossible to comprehend.


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** Bollocks.

The US market versions still have the CdS cells.

The SMD board is LABELLED:  " ROHS  TREMOLO "  !!!


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** Massive red-herring.


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** Not likely Fender will publicly reveal their premium priced  "Re-issue"
models have a stinking SMD board hidden inside. Tube purists would all puke.




.....  Phil





Re: RoHS gone MAD



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Is the fault in the tremolo section or somewhere else?

Re: RoHS gone MAD



"GeoffC"
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** The problem that I had to deal with was not related to the tremolo
circuit.

However, if that wacky SMD board ever fails, I know exactly what service
techs will do.



.....  Phil



Re: RoHS gone MAD


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LOL, probably replace it with a lamp and a CdS cell ...

Re: RoHS gone MAD


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Funny that :)

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