Search found 359 matches

by T Wilcox
Fri Jan 19, 2024 12:15 am
Forum: PCB Design
Topic: faceplates from PCB
Replies: 20
Views: 11331

Re: faceplates from PCB

IND COM graphics is where I have my non PCB faceplates printed
https://indcom.graphics/
by T Wilcox
Fri Jun 16, 2023 8:22 pm
Forum: Technical Discussion
Topic: potentiometer adjustable cold clipping?
Replies: 8
Views: 585

Re: potentiometer adjustable cold clipping?

LOL, yeah I wrote like 2 paragraphs about an adjustable cathode "Fat circuit" then looked up and saw cold clipping on the title
Guess my coffee hadn't kicked in yet
Carry on!
by T Wilcox
Thu Jun 15, 2023 4:06 pm
Forum: Technical Discussion
Topic: potentiometer adjustable cold clipping?
Replies: 8
Views: 585

Re: potentiometer adjustable cold clipping?

disregard, read cathode not clipper. DOH :oops:
by T Wilcox
Wed Jun 07, 2023 7:19 pm
Forum: Technical Discussion
Topic: Is there any simple 4 channel Latching Circuit?
Replies: 19
Views: 1216

Re: Is there any simple 4 channel Latching Circuit?

Headfirst amplification sells a MIDI 4X4 board that is setup for 4 channel operation and has the benefit of utilizing the MIDI as well if desired. Using MIDI is not necessary though https://headfirstamplification.com/pcbs-for-diy scroll down to the Midi switcher. It's $25 for the board and another $...
by T Wilcox
Mon May 01, 2023 9:27 pm
Forum: Technical Discussion
Topic: Full wave vs full wave bridge rectifier?
Replies: 48
Views: 4033

Re: Full wave vs full wave bridge rectifier?

Youll see the PT for the 100Watt 2203 has half the sec output voltage as the 2204 (like 175/175 vs 350/0/350) but uses a Full wave (no bridge) to arrive at similar B+ That sounds a bit twisted. Just to be absolutely clear... The 2203 uses a FWB (full wave bridge). The PT is 175-0-175 but the CT is ...
by T Wilcox
Mon May 01, 2023 9:07 pm
Forum: Technical Discussion
Topic: Full wave vs full wave bridge rectifier?
Replies: 48
Views: 4033

Re: Full wave vs full wave bridge rectifier?

You choose the rectifier type based on the PT voltages and the B+ desired when designing no, you order transformer which you need to follow your design goals. And, if you already have a transformer with specific voltages? Yes basically you need to know what transformer and which rectifier if you ar...
by T Wilcox
Mon May 01, 2023 7:06 pm
Forum: Technical Discussion
Topic: Full wave vs full wave bridge rectifier?
Replies: 48
Views: 4033

Re: Full wave vs full wave bridge rectifier?

You choose the rectifier type based on the PT voltages and the B+ desired when designing A good reference would be to look at and compare the schem of the Marshall 2203 and 2204 Youll see the PT for the 100Watt 2203 has half the sec output voltage as the 2204 (like 175/175 vs 350/0/350) but uses a F...
by T Wilcox
Fri Mar 03, 2023 8:03 pm
Forum: Technical Discussion
Topic: Resistors for the rest of us
Replies: 29
Views: 3142

Re: Resistors for the rest of us

For some other bulk items I use these guys. Ships from China so observe shipping charge https://www.lcsc.com/product-detail/Through-Hole-Resistors_VO-MF1W-100K-5-6T52_C2843040.html These 1W MF 500V 5% resistors are <$.03 ea They also carry Rubycon radial 450v electrolytics and Omron relays at great ...
by T Wilcox
Thu Mar 02, 2023 4:47 pm
Forum: Technical Discussion
Topic: Resistors for the rest of us
Replies: 29
Views: 3142

Re: Resistors for the rest of us

A little concerning that the Xicon CF resistors I have been getting for years just went from 100 to 5000 minimum order :shock: That said my next order I would probably buy these @ $6.40 per 100 https://www.mouser.com/ProductDetail/Royalohm/CFR01SJ0272B00?qs=sGAEpiMZZMtlubZbdhIBINZaoL9yqB51wMucGm0%2...
by T Wilcox
Thu Mar 02, 2023 12:19 am
Forum: Technical Discussion
Topic: Resistors for the rest of us
Replies: 29
Views: 3142

Re: Resistors for the rest of us

A little concerning that the Xicon CF resistors I have been getting for years just went from 100 to 5000 minimum order :shock: That said my next order I would probably buy these @ $6.40 per 100 https://www.mouser.com/ProductDetail/Royalohm/CFR01SJ0272B00?qs=sGAEpiMZZMtlubZbdhIBINZaoL9yqB51wMucGm0%2F...
by T Wilcox
Thu Jan 19, 2023 12:35 am
Forum: Technical Discussion
Topic: Switching speakers on the same amp in real time
Replies: 34
Views: 2714

Re: Switching speakers on the same amp in real time

I use a KHE 8x4 switcher for this
https://www.khe-audioelectronics.com/shop/acs-8x4
8 amp inputs and 4 cab outputs switched via MIdi foot controller
Works great
I am also able to run the cabs in pairs as well with it
Kahayan makes a similar switcher as well
by T Wilcox
Fri Dec 09, 2022 10:03 pm
Forum: PCB Design
Topic: Question about kicad.
Replies: 5
Views: 2342

Re: Question about kicad.

I'm not looking for details, I'll learn that on my own. My question is a basic one. Can Kicad allow me to create an editable schematic I can share, use it for layouts, and allow me to design a pcb file to allow a pcb building company to build my design? Reason I ask is because I don't want to dig d...
by T Wilcox
Fri Dec 09, 2022 9:24 pm
Forum: PCB Design
Topic: Getting Started With KiCad.
Replies: 5
Views: 2620

Re: Getting Started With KiCad.

I use Kicad for both PCB designs and some Faceplate and backplates for the rack preamps I build. This video is what got me started on using KiCad https://youtu.be/UOQezMJ560o After doing a faceplate I figured there wasnt too much more to learn to design a pcb so I did that next. When using eschema f...
by T Wilcox
Wed Nov 09, 2022 4:30 pm
Forum: Technical Discussion
Topic: Preamp Safety Measures (Incorrect Transformer Input Wiring)
Replies: 12
Views: 820

Re: Preamp Safety Measures (Incorrect Transformer Input Wiring)

The way I read this, the transformer has two primary windings, each has a red wire and a black wire. Call them R1, B1, R2, B2. For 115VAC you connect R1 to R2 for one side of the Mains and B1 to B2 for the other side. Normally, for 230VAC you connect B1 to R2 and apply Mains to R1 and B2. What can ...
by T Wilcox
Tue Nov 08, 2022 7:56 pm
Forum: Technical Discussion
Topic: Preamp Safety Measures (Incorrect Transformer Input Wiring)
Replies: 12
Views: 820

Re: Preamp Safety Measures (Incorrect Transformer Input Wiring)

This is a mistake I made by following the cut sheet for the Antek transformers primary There are 2 reds and 2 blacks that can be wired series or parallel for 120 or 230V What the cut sheet doesnt show is that you have to wire a specific red and specific black together which I did not do Here is the ...