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Never underestimate the obfuscating twats on diyaudio I asked a question regarding Kemet vs. Vishay-Polytech tantalum-polymer capacitors (since the Vishays are considerably cheaper and appear to

This is how my first attempt to mill a pcb stencil turned out. The aluminum sheet comes from a Burgenfels beer can.

Sourcing of currently manufactured semiconductors, even from OnSemi and other mainstream manufacturers, is log-jammed. This is a result of the perfect storm of Covid causing lines to be mothballed and

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Is there much difference between working with one of those and the standard Hakko?

 

Yes and it is not subtle. One cool thing, when you solder LED's they light up...  :)

 

The difference in power is not something I've ever noticed, even with them side by side. 

Edited by spritzer
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Since we are in this subject, I have read that Weller WTCPT also works with a coil magnet and the curie point of the tip ("Magnastat" vs. "Smartheat").

 

WTCPT housing is polycarbonate plastic and 45 Watts of output power.

 

Is there anything else that makes Metcal/Oki superior?

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I have just bought the Weller WTCPT, which is the only one readily available in my country, and I am already regretful.

 

According to Weller tech sheet that comes with the solder station:

 

“When the soldering tip is cold, a ferromagnetic temperature sensor attached to the tip attracts a permanent magnet. The magnet movement causes a shorting bar to make contact with a set of isolated magnetic contacts thereby supplying power to the heating element through the solder lugs. When the tip reaches its idle temperature, the sensor becomes non-magnetic and no longer attracts the magnet. Then a magnetic bushing attracts the magnet causing the shorting bar to break the circuit. In this manner, power to the heating elements is turned on and off automatically.”

 

 

It is like an on/off switch. That means discrete inputs of constant power.

 

Metcal instead send RF to the coil which is inside the tip and the coil loose resistance when the tip achieves the curie point, reducing the power transfer. So Metcal power transfer seems to be almost continuous and faster than the physical decoupling in Weller.

 

I will try to get a refund and go to the pain of importing the Metcal...

Edited by jgazal
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Metcal has something similar in the newer stations, sort of a stand-by feature when the wand sits in the stand.  I simply removed the magnets so it doesn't do that any more. 

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ive used a weller WTCPT for years and just bought a 3rd one. the local electronics company uses them as well which is probably where i got the idea. they've worked well for everything i've done. before that i had everyone's My First Soldering Iron, the Weller WLC100

Edited by justin
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What was so special about these black gate caps? All I remember is mikhail salivating over them.

 

only objective test i've ever seen on them was a THD comparison when using electrolytic caps on the output of a speaker amp into an 8 ohm load, so a lot of power. The Black Gates had lower THD at low frequencies as you got near the corner frequency of the cap/resistor filter that is formed. However you could get the same result by using a larger capacitance cheap electrolytic. and since Black Gates tend to be much larger than cheap electrolytics for the same capacitance, the larger capacitance cap might not use any more space

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ive used a weller WTCPT for years and just bought a 3rd one. the local electronics company uses them as well which is probably where i got the idea. they've worked well for everything i've done. before that i had everyone's My First Soldering Iron, the Weller WLC100

 

Thank you very much for the input. So I think I will give it a chance.

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  • 3 months later...

After doing some further planning I think I can get away with using 4170G washers but anyone know a good source for 4171G? No one seems to have any in stock.

 

How many do you need? I may have a few I can spare if you can't wait for stock.

Edited by GeorgeP
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Thanks Marc and George! I'm going to need around 70 for my SS T2 (T2SS?) build so probably a lot more than you can spare, but thanks anyway for offering. Dock date for Future says 9/25 which is in 3 months but I'm going to be pretty busy until then anyway and I need a bit more time to plan out the build.

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Yeah, 70 is a few more than I have as spares.

 

Were you going to do it fully SS at the board level, or use SS socket plug-ins like JoeMat did so you can opt for either tubes or SS?

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I'm doing fully SS, which is going to make things simpler. No heaters, smaller umbilicals/less wiring, less casework, the output EL34s will be replaced by the Cree 1.7kV unit spritzer posted, and the output CCSes will also use modern sand and be less complicated. There are further simplications like replacing the 2SC3381 current mirrors in the servo with MPSA42 but I bought 2SC3381s anyway and unless they test as counterfeit I will use them. Things are still in the planning stage so there might be more changes than these.

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This item is normally stocked at Walmart in the (of all places) the electronics department.  Beware though, that this is a best seller and quickly sells out.  Best to shop early on a Thursday morning after the shelves are freshly stocked!

 

Me

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Nickel for big S/E output transformers a bad idea (probably 50%)? I really like Slagle's autoformer, but Electra-Print's website points to it being a poor idea for SET output. Also any reading material about transformers will be welcome. The number of core options is head spinning. From what I have gathered so far

 

M6
M19
grain oriented silicon steel
mu-metal
amorphous
nickel
cobalt
nanocrystalline (finemet)

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I had a few studio/broadcast PA amp's gutted with Tortran 300-500va toroids, re-used them in a few integrated amp repairs. No problems. Average stuff is average. Are Sumr units still humming away?

Edited by DefQon
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Nickel for big S/E output transformers a bad idea (probably 50%)? I really like Slagle's autoformer, but Electra-Print's website points to it being a poor idea for SET output. Also any reading material about transformers will be welcome. The number of core options is head spinning. From what I have gathered so far

 

M6

M19

grain oriented silicon steel

mu-metal

amorphous

nickel

cobalt

nanocrystalline (finemet)

 

Ask 5 transformer winders and you'll get 10 answers. Short answer is nickel (which is the same as mu-metal) will saturate quickly with DC requiring a larger core. The increased core undoes nearly all, or possibly more than all, of the benefit. Some people still like it, but you'll get less bass and less power for the same size. And it costs a fortune. There are likely better ways to spend your money. But if you really want to spend it on big cores, check out Lundahl.

 

For push pull it can work better. And push pull sounds better anyway. Slagle has experimented with adding a winding for filaments that is in the opposite direction as the main winding allowing currents to cancel. No idea how successful he's been.

 

For small signal stuff with no DC, nickel or amorphous or whatever is better that steel hands down. Where the dividing line is between small signal and large is the question.

 

Anyone had experience with this mob for custom transformers?

 

http://www.tortran.com/custom_audio_transformers.html

 

Interesting. Less than an hour from me. Might be worth a trip down one of these days.

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I had a few studio/broadcast PA amp's gutted with Tortran 300-500va toroids, re-used them in a few integrated amp repairs. No problems. Average stuff is average. Are Sumr units still humming away?

 

36 month warranty ain’t too shabby for an “average” transformer?

Sumrs have there moments, I can’t say I’ve had a unit go south yet.

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I've had two SumR self destruct and it ain't pretty. 

 

Speaking of transformers, seems Keen Ocean didn't quite get my requirements.  The one in the middle should be about the same size as the ones on the left... 

 

NCOvJjRh.jpg

 

KGST transformer on the far right, each weighs a whopping 3.3KG...  :palm:

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