you can scale it down to , say , +/- 24Vdc without ill effects , considering that you don't need entire projected swing for F4 balanced
that means , considering reg losses and demands and always important mains sag og 10%.... 2x26 to 2x28Vac xformers
2x24 is , say , also useful , but better not
that means , considering reg losses and demands and always important mains sag og 10%.... 2x26 to 2x28Vac xformers
2x24 is , say , also useful , but better not
Tanks Zen
I rather get the proper one if I can still 2 X30 shuld do the trick
I am happy with that
Apreciated
Al
I rather get the proper one if I can still 2 X30 shuld do the trick
I am happy with that
Apreciated
Al
Tanks Marra
Have a pint on me that is just the one that fit the bill.
Amazing how long I have been looking around and newer found that page.
Have a pint on me that is just the one that fit the bill.
Amazing how long I have been looking around and newer found that page.
I can sell you one of my 250VA EI trafos I had custom made in Italy for the Pumpkin. I decided to be just crazy, not totally nuts and used only one. 42V secondaries...
Not sure if it fits the bill, though 😀😀. Its new and unused. I payed 80€, would sell it for 50€.
Shipping to the UK is 15 Euro from here (Germany)
Regards
Sven
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
Not sure if it fits the bill, though 😀😀. Its new and unused. I payed 80€, would sell it for 50€.
Shipping to the UK is 15 Euro from here (Germany)
Regards
Sven
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Ah, what pretty transformers, as a Fiat daily driver who's watching a Maranello car pass by.
(4 times 60VA Pollin at 1 Eurobuck each is Fiat)
(4 times 60VA Pollin at 1 Eurobuck each is Fiat)
Watch out for Airlink.
Their quality is not all that consistent, and once you get a dud, their customer service is at best "problematic".
RS components sells transformers for cheap, and with reasonable shipping charges.
Magura 🙂
Jacco - Also, if you have a power outage - it stores a lot of energy in the core so you can enjoy music about 0.5 seconds longer than with similar preamps running on torroids. 😀😀
Marras link is good, though. Very reasonable prices.
Marras link is good, though. Very reasonable prices.
Watch out for Airlink.
Their quality is not all that consistent, and once you get a dud, their customer service is at best "problematic".
RS components sells transformers for cheap, and with reasonable shipping charges.
Magura 🙂
Thanks for the tip Magura.I haven't actually bought from then yet;just remembered the link from another thread.There prices are reasonable though and they do a wide range of secondary voltages which RS or Farnell don't do.
Tanks Abraxas336
Sorry but I have to decline as I got separate box for trafos
and yours will not fit.
Tanks for posting pictures of your build and nice meter as well.
Tanks Magura I will bear that in mind I had a bad experience with traffos for F5 and tok loads of time to sort out.
Sorry but I have to decline as I got separate box for trafos
and yours will not fit.
Tanks for posting pictures of your build and nice meter as well.
Tanks Magura I will bear that in mind I had a bad experience with traffos for F5 and tok loads of time to sort out.
Hi BKsabath,
These are the transformers I bought for my Pumpkin, not too expensive
Buy Chassis Mounting Transformers Frame mount transformer,75VA 2x50V o/p RS 10-5879 online from RS for next day delivery.
These are the transformers I bought for my Pumpkin, not too expensive
Buy Chassis Mounting Transformers Frame mount transformer,75VA 2x50V o/p RS 10-5879 online from RS for next day delivery.
It has been A long time since last post
I got a Shunty working fine yesterday the other just wont have it.
I have most probably messed up the PCB when desoldering components for the third time.
I am going to start and probably bench test Pumpkin today.
Questions
What gain you use for F5?
I am thinking 4 may be the best compromise so R5 R6 at about 47K
As those are about 1/2 then C1 C2 = 10P ?
I got a Shunty working fine yesterday the other just wont have it.
I have most probably messed up the PCB when desoldering components for the third time.
I am going to start and probably bench test Pumpkin today.
Questions
What gain you use for F5?
I am thinking 4 may be the best compromise so R5 R6 at about 47K
As those are about 1/2 then C1 C2 = 10P ?
Long time since
Got my Pumpkin getting there.
Got same truble with setting up ofset sems to go from +3 to - X V as WR1 turns atiny winy fraction so I put on same red and green components.
Did I do this right (please remember I have attention span of Dodo site of Trillobite and move swings that would make Marvin estatic)
so when one vrites turn pot to zero it takes me quite a lot to decide to ground the imputs and still wonder if is right.
So question :
Are green and red componets in right place?
And by the way
Prety crappy square
Prety good square
Prety nasty mod (green and red dudas)
Got my Pumpkin getting there.
Got same truble with setting up ofset sems to go from +3 to - X V as WR1 turns atiny winy fraction so I put on same red and green components.
Did I do this right (please remember I have attention span of Dodo site of Trillobite and move swings that would make Marvin estatic)
so when one vrites turn pot to zero it takes me quite a lot to decide to ground the imputs and still wonder if is right.
So question :
Are green and red componets in right place?
And by the way
Prety crappy square
Prety good square
Prety nasty mod (green and red dudas)
Attachments
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sorry
will look tomorrow
me brain is on 10% of usual 10%
had 560km of driving today , with air conditioner on all the time
it would be more enjoying that I took bicycle for that trip , instead of car

in any case - whatever you do , that devily vegetable must be in final case , with lid on
usual drill as with any Papa's creature - temp equilibrium is 70% of story
will look tomorrow
me brain is on 10% of usual 10%
had 560km of driving today , with air conditioner on all the time
it would be more enjoying that I took bicycle for that trip , instead of car

in any case - whatever you do , that devily vegetable must be in final case , with lid on
usual drill as with any Papa's creature - temp equilibrium is 70% of story
WHAT VEGETABLE?
Fruty thing work first time preaty steady out of box down to cuple of millivolts between T1 an T2 just sitting on bench.
Can't wait for second chanell to mesure up and then in the box
PS you yes quite right...
Take your time me going for spatcha now.
Fruty thing work first time preaty steady out of box down to cuple of millivolts between T1 an T2 just sitting on bench.
Can't wait for second chanell to mesure up and then in the box
PS you yes quite right...
Take your time me going for spatcha now.
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