Hybrid ODS rack preamp

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groovtubin
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Re: Hybrid ODS rack preamp

Post by groovtubin »

Hahaha..looks lie you use the palm of your hand as well, to level off preamp tubes!
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M Fowler
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Re: Hybrid ODS rack preamp

Post by M Fowler »

I always install bad tubes when soldering to the pins. Habit.
jam-mill
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Re: Hybrid ODS rack preamp

Post by jam-mill »

Mark,
This build looks really nice for "design on the fly".

Anxious to see the completed project.

-jack
John 15:12-13
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Re: Hybrid ODS rack preamp

Post by brewdude »

On the schematic you posted, are B+1, B+2 and B+3 unused/unloaded?
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M Fowler
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Re: Hybrid ODS rack preamp

Post by M Fowler »

B+1, B+2, and B+3 I'm using. That schematic is just a representation of what I might follow.

I don't create schematics or layouts, you guys are so talented that way, not me.
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M Fowler
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Re: Hybrid ODS rack preamp

Post by M Fowler »

Got the specs from Magnetic Components:

You're in luck. The 6.3V winding of our 40-17371 is rated at 600mA. The 200V winding is rated at 6mA DC.

Mark
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martin manning
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Re: Hybrid ODS rack preamp

Post by martin manning »

Hey that’s great! Is there a link to the MC spec sheet? That PT might be a good option for a D’lator.
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M Fowler
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Re: Hybrid ODS rack preamp

Post by M Fowler »

Martin I tried to find one and could not so I will reply to the MC and see if he will send me the transformer spec sheet to post. I cannot remember where I found this one and went through my stack of receipts which did not yield the results of where I bought this PT. The Button I know where that came from Tubedepot but not this MC PT.

Mark
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martin manning
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Re: Hybrid ODS rack preamp

Post by martin manning »

I looked on their site and came up empty. You might mention to them that the guitar amp crowd would be interested in that unit for tube pedals, preamps, and the like. It appears it fits in a 1u rack chassis, correct?
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M Fowler
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Re: Hybrid ODS rack preamp

Post by M Fowler »

Correct it is fits perfectly in the I unit rack enclosure that is why I bought the PT originally.

I searched the MC site and all over the place to try figure out how I came across this PT.

I think it was a sale item on one of my usual amp parts sites.

I did request the PT spec sheet and will ask them why it is not on their website but I think it is a custom unit so not listed.
I will note to them that the community could benefit from this PT.

Mark
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martin manning
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Re: Hybrid ODS rack preamp

Post by martin manning »

Thanks Mark!
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M Fowler
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Re: Hybrid ODS rack preamp

Post by M Fowler »

Martin,

MC said this is for sale at Tubedepot but they are showing the old PT specs on Tubedepot website.

I am assuming this is a vendor spec transformer "custom" order so that is why when I asked for spec sheet they referred me to Tubedepot.

I replied that Ampgarage members are interested in this transformer that is not listed on MC website so we will see what happens.

Mark
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M Fowler
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Re: Hybrid ODS rack preamp

Post by M Fowler »

MC 40-17371 PT preamp.pdf
Martin,

Tubedepot reply was the higher mA rated PT was specially requested through MC for a Tubedepot project and they said they never received a spec sheet so we will have to change the Button spec sheet to reflect the higher mA ratings for HT secondary and Filament 6.3v windings.

Mark
button_xformer.pdf
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martin manning
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Re: Hybrid ODS rack preamp

Post by martin manning »

Ok so if I order a Button Tx from Tubedepot will get the MC part, or the Heyboer? The MC will be good for a preamp such as you are building, but the B+ will be ~280, so too low for the D’lator spec.
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pompeiisneaks
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Re: Hybrid ODS rack preamp

Post by pompeiisneaks »

I won't go into the deep details, but I'll just warn, TubeDepot has possibly the worst customer service I've used besides Sprint, so be wary of them, and hope nothing goes wrong. If you want more detail I'll do it over PM instead of hashing it out here.

~Phil
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