Pass DIY Addict
Joined 2000
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Ha, this is always the place where I get the most nervous 😉. I spend copious amounts of time checking and double checking my wiring before the first power up, always afraid that I’ll blow something up the first time. Do you have a dim bulb tester? Those a great tools to a first power up.
You might want to consider twisting all of your AC wires, the primary and secondary wires on the transformer. You have them neatly zip tied together, but there will be reduced AC hum emitted from the wires if they are twisted well. Also, what gauge wires run from your bridges to your cap board? They look a little thin and you might benefit from heavier gauge wire as the path to the first cap represents the largest currents in the amp.
Edit:
Another potential benefit is to turn your transformer right-side-up (it is presently upside down). This keeps the ac wires closer to the ground plane of the chassis instead of being up in the air.
You might want to consider twisting all of your AC wires, the primary and secondary wires on the transformer. You have them neatly zip tied together, but there will be reduced AC hum emitted from the wires if they are twisted well. Also, what gauge wires run from your bridges to your cap board? They look a little thin and you might benefit from heavier gauge wire as the path to the first cap represents the largest currents in the amp.
Edit:
Another potential benefit is to turn your transformer right-side-up (it is presently upside down). This keeps the ac wires closer to the ground plane of the chassis instead of being up in the air.
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Pass DIY Addict
Joined 2000
Paid Member
16 gauge should be ok. I usually use 14g - it just looked extra thin next to the secondary wires from the transformer.
It looks like you posted your reply while I was editing my original post - turn your transformer right side up as well.
It looks like you posted your reply while I was editing my original post - turn your transformer right side up as well.
What type of connector? From previous pics, I just use something like this. There are 100s of variants.
https://www.amazon.com/Klein-Tools-...43049767&sprefix=electrical+cr,aps,102&sr=8-5
Make sure the size of the connector (color coded) is suited to the wire gauge, and that you crimp using the matching color on the tool. The ratcheting is nice b/c it reduces the chances of too little (loose connection) or too much (cut through the insulation or fracture wire/connection) pressure.
Looking good, BTW.
https://www.amazon.com/Klein-Tools-...43049767&sprefix=electrical+cr,aps,102&sr=8-5
Make sure the size of the connector (color coded) is suited to the wire gauge, and that you crimp using the matching color on the tool. The ratcheting is nice b/c it reduces the chances of too little (loose connection) or too much (cut through the insulation or fracture wire/connection) pressure.
Looking good, BTW.
I got that crimper today and I must be doing something wrong, because the wire pulls right out of the connector after crimping. I'm using the yellow color on the heavy wire coming out of the transformer. The wire is too thick to go with the blue size. Any suggestions?
The secondaries of your Antek transformer should work nicely with the yellow color coded connectors. Without some really detailed pics, it would be tough to tell.
In order of guessing and knocking things down the list -
1) Gauge of wire too small. I think those Antek secondaries are either 10 or 12 AWG. You can verify.
2) Diameter of connector too big - yellow should work well with 10 to 12 AWG. Blue should work well with 14-16. Check your packaging.
Those are unlikely, but you have to rule them out. Below is maybe a bit more likely.
3) Stripped wire properly. Make sure you've stripped off enough insulation to where the crimp metal (in the connector) to wire. You don't want the crimp on the insulation at all.
4) Make sure you're crimping far enough down to achieve #3. Don't crimp the "skirt".
If you want, strip off the plastic of one of the connectors and crimp without it. You should be able to see the metal crush around the wire. Also, it may give you a better visual of where on the connector it's best to place the tool / make the crimp. You should literally feel the metal collapse under the crimp.
I tried to find a decent YouTube vid with no success. I wish there was a definitive answer. If in doubt, strip off the plastic and solder them.
Edited to add - also make sure you take a look at the instructions for that crimper. It has an adjustable ratcheting force. It may not be your issue, but set it to the highest force and see if that helps.
In order of guessing and knocking things down the list -
1) Gauge of wire too small. I think those Antek secondaries are either 10 or 12 AWG. You can verify.
2) Diameter of connector too big - yellow should work well with 10 to 12 AWG. Blue should work well with 14-16. Check your packaging.
Those are unlikely, but you have to rule them out. Below is maybe a bit more likely.
3) Stripped wire properly. Make sure you've stripped off enough insulation to where the crimp metal (in the connector) to wire. You don't want the crimp on the insulation at all.
4) Make sure you're crimping far enough down to achieve #3. Don't crimp the "skirt".
If you want, strip off the plastic of one of the connectors and crimp without it. You should be able to see the metal crush around the wire. Also, it may give you a better visual of where on the connector it's best to place the tool / make the crimp. You should literally feel the metal collapse under the crimp.
I tried to find a decent YouTube vid with no success. I wish there was a definitive answer. If in doubt, strip off the plastic and solder them.
Edited to add - also make sure you take a look at the instructions for that crimper. It has an adjustable ratcheting force. It may not be your issue, but set it to the highest force and see if that helps.
Yea it was the force adjustment. I put it up to the highest and it wouldn't close all the way, so I'll back it off a bit. Thanks.
I still can't get it to crimp, not sure what I'm doing wrong. The connector pulls right off no matter how hard I squeeze. Does the connector need to be in a certain position in the crimper?
Something must be odd that I'm missing. I know you know how to crimp, but the tool just should "work". Below is showing no indentation at all.
Jaws go here.
That pic is pre-crimp. Maybe I'll play around with the force setting but there's no way to tell where it's set since it spins in circles.
Thomas and Betts Sta-Kon. Best crimper ever made. Ask the professionals.
https://www.supplyhouse.com/Sta-Kon...-JcU2I7pJQcOsp-Y2XvbKMHmuB1JnejoaAgWNEALw_wcB
https://www.supplyhouse.com/Sta-Kon...-JcU2I7pJQcOsp-Y2XvbKMHmuB1JnejoaAgWNEALw_wcB
There's a plus and minus on the tool. Correct, there's no "indicator" for exact position repeatability, but you can set the relative position of the gear. If you'd like, put a dot of paint on the teeth as a reference. Blue dot for fave blue setting, red for fave red setting, yellow for yellow. You get the picture. Hopefully, giving a bit more clamping force will do the trick for you.
Totally unrelated to crimping. Basically just here to watch and show support. Chiming in on one other thing, just in case (and for my knowledge also). I can't remember if you said which version of the F5T you're shooting for. Mainly, I'm wondering what rails / Iq you're shooting for. I can't see the transformer label, and I'm not sure re: how much of a FAB you are / and if this'll be a room heater.
Either way... have someone smarter than I verify if your PSU filter resistors aren't going to get too toasty and/or are suitable. For the V2 (as an example), Nelson shows a suitable PSU having 7, 3W resistors in parallel. 4, 5W might be groovy, or just stuff a few more 3W into the optional spots. Again, after someone smarter than I verifies or says I'm off base.
Either way... have someone smarter than I verify if your PSU filter resistors aren't going to get too toasty and/or are suitable. For the V2 (as an example), Nelson shows a suitable PSU having 7, 3W resistors in parallel. 4, 5W might be groovy, or just stuff a few more 3W into the optional spots. Again, after someone smarter than I verifies or says I'm off base.
I'm building a V2 with 32V rails. I suppose there's no harm in adding more of the 3W resistors.
Lot of wires in this thing, and the wire I chose is stranded but still kind of stiff.
😀
Nope. Nelson specifically says "...but the resistance has been lowered to 0.067 ohms to ensure low losses". That might imply 7, 0R47 in parallel. 😀
Looking good!
Last little bit. Don't know why I didn't bring this up with the filter resistors... just didn't think of it. Again... someone smarter than I will need to give you real "advice" vs. me just pointing out observations and asking questions.
He says just before that... ",and you see that we are using lots more capacitors."
The PSU has 8 caps total. 4 on each side of the resistors. Assuming (WAG Alert!) that he uses the same 15kuF common in commercial FW amps ... that's 60kuF on each side. You have 44k on each side of the resistors for each rail. In PSUD, you add a bit of ripple with the lowered resistance, and with less capacitance, that's another increase in ripple. Does that ripple matter? Did I do the simulation correctly? Can't answer either of those questions myself.
Again... don't want to blow smoke where there's no fire. I'm just hoping one of the super-smart FABs out there reads this and perhaps chimes in.
Edits for clarity and mistype re: total capacitance. Gotta get one more coffee. 😀
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I'm just going by the PS schematic in the F5 Turbo article which shows 7 .47-ohm 3W resistors. I also have 88kuF of capacitance on each rail.