I am making good progress in my build. Power supplies up and running and tested. So I turned my attention to the F5 boards (F5 V2.0 from diyAudio Store). Started out by reviewing the excellent build guide. I managed to confuse myself about the orientation of the LED.
The instructions say the longer lead is positive and goes in the round pad. The LED in the photo is translucent so I can see that is in fact the orientation the builder put it in.
However, I thought the convention was that the longer lead (anode) goes in the square hole. The silkscreen on the board shows the anode on the right, which is the square hole. I traced the leads on the board and I think the round hole is connected to ground and V+ is connected to the square hole through R35.
Normally I would just build the board, hook it up to the power supply and see if the LED is lit, reverse it if it doesn't light and then fret if it doesn't work either way. But this is my first solid state project so I am trying to be extra careful.
Any clarification would be appreciated.
Thanks
dante550
The instructions say the longer lead is positive and goes in the round pad. The LED in the photo is translucent so I can see that is in fact the orientation the builder put it in.
However, I thought the convention was that the longer lead (anode) goes in the square hole. The silkscreen on the board shows the anode on the right, which is the square hole. I traced the leads on the board and I think the round hole is connected to ground and V+ is connected to the square hole through R35.
Normally I would just build the board, hook it up to the power supply and see if the LED is lit, reverse it if it doesn't light and then fret if it doesn't work either way. But this is my first solid state project so I am trying to be extra careful.
Any clarification would be appreciated.
Thanks
dante550
The shorter lead usually marries up with the flat on the LED envelope to denote the Cathode of the device.
The symbol on the board looks like an arrow head, the point of the arrow is the Cathode.
The symbol on the board looks like an arrow head, the point of the arrow is the Cathode.
LEDs are not good at blocking reverse current.
Inserted the wrong way can blow them.
The Bar on the schematic matches the Bar marking on the diode and the flat Bar on LED
The flat Bar is removed plastic and matches the bit of lead out that is removed to create the shorter lead out.
A translucent LED can be seen to have a Big electrode. If you equate this Big electrode (reflective cup) to the Bar you are OK
Inserted the wrong way can blow them.
The Bar on the schematic matches the Bar marking on the diode and the flat Bar on LED
The flat Bar is removed plastic and matches the bit of lead out that is removed to create the shorter lead out.
A translucent LED can be seen to have a Big electrode. If you equate this Big electrode (reflective cup) to the Bar you are OK
The long lead should go to +, so if I read your description correctly, I think you are right that is should have been the square hole. The LED is not a critical part amp though, so focus on not making shorts and going slowly with the pots and you should be fine.
I can't remember little details like square pads and round pads.
I need acronyms and such to help me remember.
bbroygbvgw = ?
I need acronyms and such to help me remember.
bbroygbvgw = ?
Billy Bunter Rapes Our Your Girls But Virgins Go Without - The resistor colour code.
An unethical but easily remembered anacronym.
For LEDs I remember the Kicking Cathode and that kicks a memory that that is the shorter lead.
An unethical but easily remembered anacronym.
For LEDs I remember the Kicking Cathode and that kicks a memory that that is the shorter lead.
Last edited:
Black Brown Red Orange Yellow Green Blue Violet Grey White
The resistor colour code from 0 to 9 for the first two or three digits.
tolerance and tempco and multiplier are different. Although Brown (1) works for tolerance of +-1%
The resistor colour code from 0 to 9 for the first two or three digits.
tolerance and tempco and multiplier are different. Although Brown (1) works for tolerance of +-1%
Here in the States, our similarly offensive mnemonic device is: Bad Boys Rape Our Young Girls, But Violet Gives Willingly. I suppose they both benefit from being memorable.
thanks for all the feedback...
I have my first amp almost complete. building a pair (biamping).
sadly schedule delays completion until next week.
fingers crossed hoping for no smoke and an easy bias adjustment.
dante
I have my first amp almost complete. building a pair (biamping).
sadly schedule delays completion until next week.
fingers crossed hoping for no smoke and an easy bias adjustment.
dante
Powered it up today...
I powered up the first completed amp. Got the bias set. All very nice. Only the quickest of listens through orb speakers (no need to cry of they fry).
So far so good.
Second one will be a lot easier and quicker.
Can't wait to hear them in the living room.
dante
I powered up the first completed amp. Got the bias set. All very nice. Only the quickest of listens through orb speakers (no need to cry of they fry).
So far so good.
Second one will be a lot easier and quicker.
Can't wait to hear them in the living room.
dante
do NOT do the misstake of thinking the second one is easier and do it quicker. THAT's when mistakes are done.
Second amp complete!
The second amp took a bit longer than expected. I goofed up my order. Came up short a couple resistors.
After that setting the bias was easy as before. Sounds very nice. I am biamping a pair of ProAc Response2 speakers with a marchand tube crossover.
The F5 amps give me a bit more oomph (previously biamped with a 300B se amps), they are dead silent and sound great.
I really appreciate the help I got from this forum. I didn't ask all that many questions since there was so much great information available. I did arrive kind of late to the F5 scene after all the brave souls blazed the trail ahead of me.
Thanks, thanks and thanks.
dante
The second amp took a bit longer than expected. I goofed up my order. Came up short a couple resistors.
After that setting the bias was easy as before. Sounds very nice. I am biamping a pair of ProAc Response2 speakers with a marchand tube crossover.
The F5 amps give me a bit more oomph (previously biamped with a 300B se amps), they are dead silent and sound great.
I really appreciate the help I got from this forum. I didn't ask all that many questions since there was so much great information available. I did arrive kind of late to the F5 scene after all the brave souls blazed the trail ahead of me.
Thanks, thanks and thanks.
dante
- Status
- Not open for further replies.