These are all encapsulated. The actual transformer itself is smaller.
The "shielding" is a bit vague -- magnetic or electrostatic, or both ?
Europeans want 230Vac primary, or 2x115Vac.
The housing can in principle take all three. We are not tight to the last mm or 2.
Go to the Plitron page for audio transformers, and look at their spec sheets as a reference.
Patrick
The "shielding" is a bit vague -- magnetic or electrostatic, or both ?
Europeans want 230Vac primary, or 2x115Vac.
The housing can in principle take all three. We are not tight to the last mm or 2.
Go to the Plitron page for audio transformers, and look at their spec sheets as a reference.
Patrick
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both myself and john contacted richard earlier separately, (john just for himself by the looks of it). I mentioned that I would possibly take one in a can, but that perhaps to get a quote for the forum for one with a core band only for this quote, not sure what John asked for. I also specified to him just before to do one without a can just with mounting hardware to cover all bases. I dont normally get electrostatic shielding, because I usually get fully encapsulated
I would say this is based on johns request based on the 240v detail (hadnt noticed that) but he sent the email to both of us simultaneously since we are friends and both in OZ. I asked for dual primaries. but I will follow up now to make sure he includes that. I normally get 240v single primary too, so maybe he just assumed thats what I wanted this time too. anyway it should be all cleared up by the time he does the actual quote; i'm off to bed now its 6.37am night!
I would say this is based on johns request based on the 240v detail (hadnt noticed that) but he sent the email to both of us simultaneously since we are friends and both in OZ. I asked for dual primaries. but I will follow up now to make sure he includes that. I normally get 240v single primary too, so maybe he just assumed thats what I wanted this time too. anyway it should be all cleared up by the time he does the actual quote; i'm off to bed now its 6.37am night!
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If you want to find out why I don't like cans, google to see
1) what mechanical stress will do to the permeability of Tx steel bands
2) why do these materials need hydrogen annealing
3) how much encapsulation epoxy will shrink on curing
4) what are the coefficients of thermal expansion for steel, copper, and epoxy (curing takes place at about 80°C).
But, your choice.
If Plitron also sells them encapsulated, they must also be of some good.
Patrick
1) what mechanical stress will do to the permeability of Tx steel bands
2) why do these materials need hydrogen annealing
3) how much encapsulation epoxy will shrink on curing
4) what are the coefficients of thermal expansion for steel, copper, and epoxy (curing takes place at about 80°C).
But, your choice.
If Plitron also sells them encapsulated, they must also be of some good.
Patrick
right, termination with 2x115v primaries is the same cost, so 240v, 230v or 2 x 115v is all the same. totally encapsulated is 128USD, with core band and no box, plus mounting hardware is 99USD. electrostatic screen between primary and secondary is extra. these are just single prices, if people would like me to get a GB together let me know and we'll go from there. we have managed to have it so each one is sent directly out to the buyer and a special price and known spec is used for people involved in the project. or can be worked another way . anyway any more is too OT and a thread should be started. so i'll just leave it there.
Sorry for the slow response Patrick. I'm planning to build the supply within the box that you are offering for the FX5.
I've also used Sumr transformers before and I was happy with their service and product. Their prices are reasonable, and they willing to customize a unit for you needs. I was planning to use one for their transformers unless a GB was setup.
I would like to tell everyone here that I have got the resistor proposal back from Texas Components. They have offered the following specifications:
Texas Components Part Number TX2599, which describes the following array of components:
-- One set of eight resistors,
-- Each resistor in a TX220 or TX221 style package, with each resistor in the set matched to within ±0.5% of the resistance value of every other resistor in the set
-- All resistors in the set to be accurate to within ±5.0% of 0R22 ohms when measured at a point 0.5 inches from the package outline in the case of the TX220, or between to two center leads in the case of the TX221 package. Data sheets of the TX220z and the TX221z are attached for your convenience
-- Each resistor capable of a current of 4.0 amperes and a power rating of 4.0 watts when mounted on a heat sink whose temperature does not exceed 80ºC
-- Temperature coefficient of resistance in the TX221 package to be ±0.2 ±2.3 ppm/ºC over the temperature range of 0ºC to 80ºC; and to be ±0.2 ±20.0 ppm/ºC in the TX220 package.
Unit pricing will be $365.00 per TX2599 set, in quantities of 5 or more TX2599 sets per release. FOB our facility in Houston Texas.
they can raise that current, as they misunderstood a previous email, and they have worsened the specs to meat what I had said previously. Any comments. Should I proceed with a GB?
Texas Components Part Number TX2599, which describes the following array of components:
-- One set of eight resistors,
-- Each resistor in a TX220 or TX221 style package, with each resistor in the set matched to within ±0.5% of the resistance value of every other resistor in the set
-- All resistors in the set to be accurate to within ±5.0% of 0R22 ohms when measured at a point 0.5 inches from the package outline in the case of the TX220, or between to two center leads in the case of the TX221 package. Data sheets of the TX220z and the TX221z are attached for your convenience
-- Each resistor capable of a current of 4.0 amperes and a power rating of 4.0 watts when mounted on a heat sink whose temperature does not exceed 80ºC
-- Temperature coefficient of resistance in the TX221 package to be ±0.2 ±2.3 ppm/ºC over the temperature range of 0ºC to 80ºC; and to be ±0.2 ±20.0 ppm/ºC in the TX220 package.
Unit pricing will be $365.00 per TX2599 set, in quantities of 5 or more TX2599 sets per release. FOB our facility in Houston Texas.
they can raise that current, as they misunderstood a previous email, and they have worsened the specs to meat what I had said previously. Any comments. Should I proceed with a GB?
> it is 4* 0.22 ohm resistors per amp, and not 2* 0.22 ohms and 2*0.18 ohm?
4x 0R22 is default.
The other values (deliberate detune from symmetry) is to trade 2nd harmonics against 3rd, and require a balanced IN/OUT THD analyser and a spectrum analyser.
The exact value is unknown & depends on P to N match.
You can always detune later on by soldering a 3R resistor in parallel, as NP & I did, for different reasons.
Patrick
PS I believe a set of 8 N-P matched Toshiba MOSFETs costs USD 112, right ?
.
4x 0R22 is default.
The other values (deliberate detune from symmetry) is to trade 2nd harmonics against 3rd, and require a balanced IN/OUT THD analyser and a spectrum analyser.
The exact value is unknown & depends on P to N match.
You can always detune later on by soldering a 3R resistor in parallel, as NP & I did, for different reasons.
Patrick
PS I believe a set of 8 N-P matched Toshiba MOSFETs costs USD 112, right ?
.
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For those who think Futaba MPC74 is not their cup of tea, for whatever reasons, but may not have the deep pockets for TZ220,
the Caddock MP930 (0R2) is 2.50 Euro each for a quantity >10 at Buerklin, or 7 USD at Partsconnexion.
Unmatched, of course. But I am sure you can GB and group match.
You still need heat sinking on those.
Not on MPC74s. They are free standing (and much less than 1 Euro a piece).
Patrick
the Caddock MP930 (0R2) is 2.50 Euro each for a quantity >10 at Buerklin, or 7 USD at Partsconnexion.
Unmatched, of course. But I am sure you can GB and group match.
You still need heat sinking on those.
Not on MPC74s. They are free standing (and much less than 1 Euro a piece).
Patrick
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I just paid USD $ 64 for SK1530s/2SJ201s 4 matched pairs to 0.01V. I purchased them from Zhou Fang.
Yes I know, Im not knocking anyone who helps out with a GB etc, but I thought it was funny that someone (texas) would bother to quote that much for a resistor, unless the request came in on Nasa lettter head
I understood that as "unit price of $365.00" meant per piece. Per set is a bit better but still a bit much for me.
What advantage (other than perhaps you already have them) ?
I don't understand the reluctance to use MPC74.
It is low distortion bulk foil (hence low inductance) for audio.
It is good enough for Accuphase.
Good enough for me. Not good enough for you ?
Patrick
No reluctance here. I actually have some on order but I also have a stack of vishay dale resistors that I would like to put to good use. It would be nice to compare them.
Sorry I can't help myself. I have to experiment with everything.
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