Hello. Just finished building F5T v2 and setting the bias. I was able to set bias without any issue on 1 channel. The other channel is having issues. With P1 and P2 zeroed I'm getting voltage on the speaker output and the Variac is only at 10 volts. Within 5 minutes I'm seeing 100 degF at the center pin of D2 using infrared thermometer. The rest of the boards show 75 degF. I shut the Variac off and figured something can't be right. Does anyone have any ideas for me on how to troubleshoot the problem? Is the Rectifier bad? How do I verify that the Rectifier at D2 is good?
If someone wanted an awesome chassis for this amp here it is
https://www.diyaudio.com/forums/pass-labs/360807-ultimate-4u-500mm-chassis-38.html#post6410433
https://www.diyaudio.com/forums/pass-labs/360807-ultimate-4u-500mm-chassis-38.html#post6410433
Problem solved. The Transistors at Q3, Q4 and Q6 were bad. They didn't look bad, no cracks, fire etc... but when I tried to remeasure vgs I got nothing out of them. Weird!
F5Tv2 or 3 Balanced Input ready?
Quick Question - Can F5Tv2 or 3 be used in Balanced input without any mods? We normally short Gnd and Link for -ve in.
Quick Question - Can F5Tv2 or 3 be used in Balanced input without any mods? We normally short Gnd and Link for -ve in.
Hello, I am new here and read through the whole thread. Would it be safe to say it's easier to build a balanced v3 monoblock as opposed to trying to shoehorn a balanced v2 into a single 5U chassis?
What is the screw down terminals between the transformer and the psu? Also, from the power supply build thread, there’s another little square thing between the transformer and that power board. Do I need that thing? Thanks!
Yes you need that thing. There are actually TWO of them in the picture. One has a gray wire attached to it, and the other has a yellow wire attached to it.
Rectifier bridges, covert ac output from transformers to a full rectified signal which is the input to the smoothing capacitor back and filtering RC circuit
thank you Mark Johnson, chuck23, and Keremito
In the 6l6 power supply build thread, he mentions "Feel free to snap off the diode section and use monolithic bridges. They work and sound great!" right below the pic I circled. I checked the BOMs for both F5T (v2 pdf link), and the power supply BOM (xls link) but none of them mention this part. Can someone suggest a specific part at mouser or digikey that will fit the bill?
Also, looking carefully over the pictures in this F5T build guide, 6l6 doesn't use bridge rectifiers. I only see them on the power supply circuit build guide thread.
In the 6l6 power supply build thread, he mentions "Feel free to snap off the diode section and use monolithic bridges. They work and sound great!" right below the pic I circled. I checked the BOMs for both F5T (v2 pdf link), and the power supply BOM (xls link) but none of them mention this part. Can someone suggest a specific part at mouser or digikey that will fit the bill?
Also, looking carefully over the pictures in this F5T build guide, 6l6 doesn't use bridge rectifiers. I only see them on the power supply circuit build guide thread.
Do you want to use the discrete diodes/heatsinks, or the 4-terminal bridges? It's your choice. They both work and get the job done.
ah - I can stick with the terminal bridge
in lieu of the bridge rectifier? That sounds AOK to me! I'll do the terminal bridge. Thanks! Wanted to make sure I wasn't missing anything important.
in lieu of the bridge rectifier? That sounds AOK to me! I'll do the terminal bridge. Thanks! Wanted to make sure I wasn't missing anything important.
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Terminal bridge? What's that?
Your photo didn't post...
EDIT: Ok, I see your photo.
That terminal block has wiring on the primary side of the transformer and the AC mains, thermistors and line cap. Has nothing to do with rectification. You'll need that regardless.
Your photo didn't post...
EDIT: Ok, I see your photo.
That terminal block has wiring on the primary side of the transformer and the AC mains, thermistors and line cap. Has nothing to do with rectification. You'll need that regardless.
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Howdy! I'm up in Bellingham and also about to embark on this same adventure. This is gonna be fun!!
Antek 6224 Snubber Capacitors
Hi-
I have scoured the forums, but for the life of me I can't find any subber capacitor information for the Antek 6224 transformer. 6L6, I know you used this anchor for the build guide, could you please share the components you used for snubbers? Thanks in advance.
-Wes
Hi-
I have scoured the forums, but for the life of me I can't find any subber capacitor information for the Antek 6224 transformer. 6L6, I know you used this anchor for the build guide, could you please share the components you used for snubbers? Thanks in advance.
-Wes
I am apparently confused... I am actually asking about the components on the terminal block (conveniently circled above)
Awesome, thanks! I happened to ask a similar question in the main thread for these boards and this seems to answer it. Everything but the actual diodes+heatsinks on the rectifier boards is totally optional yeah?
If you get a chance to take a look at my other questions in the main thread for the boards I'd hugely appreciate it. Of course zero worries if not!
Thanks again!