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Tubes and Hybrids / Re: Help with Hybrid Design
« Last post by phatt on December 30, 2020, 03:38:23 AM »Agree with G1, 
Adding;
Well the data sheet tells it as I suspected,, It's Not an *isolated 115v Tx*
It states very clearly it has 2x115v primaries and 2x 7V secondaries.
So unless I've lost it,
,the only way one could get enough HT to run a valve is from one of the primary windings which means it's a death trap waiting to happen as the circuit runs off the primary. ARRRRGH!!!!
OK sure there are tons of old radio circuits that did indeed run direct from mains but most of those old units where bakalite cases and one would never come into contact with the circuit under normal use but this is an electric guitar amplifier and you ARE in direct contact with part of that circuit so if something fails you could end up Dead.
If you want to build it that is your call but I'm writing this to warm other non teck savvy folks that it's a death trap waiting to happen.
Be very careful grabbing ideas off the net some are really bad designs.
To attain HT for a small valve amp there are much SAFER ways,, here is a better option for High voltage, uses back to back Tx's.
https://valveheaven.com/diy-amp-designs/the-lamington-junior/the-lamington-junior-design/
The added bonus is that it uses a 12Volt wall wart which keeps you a long way away from dangerous main voltages.
HTHelps, Phil.

Adding;
Well the data sheet tells it as I suspected,, It's Not an *isolated 115v Tx*
It states very clearly it has 2x115v primaries and 2x 7V secondaries.
So unless I've lost it,

OK sure there are tons of old radio circuits that did indeed run direct from mains but most of those old units where bakalite cases and one would never come into contact with the circuit under normal use but this is an electric guitar amplifier and you ARE in direct contact with part of that circuit so if something fails you could end up Dead.
If you want to build it that is your call but I'm writing this to warm other non teck savvy folks that it's a death trap waiting to happen.
Be very careful grabbing ideas off the net some are really bad designs.

To attain HT for a small valve amp there are much SAFER ways,, here is a better option for High voltage, uses back to back Tx's.
https://valveheaven.com/diy-amp-designs/the-lamington-junior/the-lamington-junior-design/
The added bonus is that it uses a 12Volt wall wart which keeps you a long way away from dangerous main voltages.
HTHelps, Phil.