Avalon - U5 DI Preamp

Madmax · Post by **Madmax** » 07 Oct 2021, 19:49

Hi Karl,
thanks for the help! The schem you sent confirms what I had figured out is the signal path, but at the end of that first bit I still have a signal, soon after that I lose it... I've got a test tone running off my DAW (1kHz sine), oscilloscope is hooked up. Very simple chinese one (seems we've got a bit in common

) I know roughly where my signal gets lost, but I haven't been able to track it down to a specific part. And I hate two-sided PCBs

Funny thing is: of Q8 and Q9 only one carries a signal (same with Q12 and 13), later there is no signal anymore.

As it's open anyway I might just do the caps along the way, can't go wrong even if none are visibly bulging or blown. Guess mine are around 20 years old...

I'll post my solution as soon as I've got it going again (or if...)!

Madmax · Post by **Madmax** » 10 Apr 2022, 08:03

Solved!
It was one little resistor that had blown. Not visibly from the outside, not charred or anything. Just broke. Now it's up and running again

Thanks for all the input!
Greetings, Max

Jarno · Post by **Jarno** » 10 Apr 2022, 21:18

Nais!

bbkassel · Post by **bbkassel** » 29 Jan 2023, 14:49

Phil Smith wrote: ↑23 Jul 2015, 20:31 Just quick snap shots of current progress..
Almost all traces on the main board, all top layer traces on tone and boost boards and my vision ( ) of boost pcb bottom layer (the boost board is pretty simple)
The chip on the tone board (RN1) is just resistor network MDP16-03 10?G with 8 resistors (pin 1-9, 2-10, 3-11 ... 8-16). According to its datasheet ( http://www.vishay.com/docs/31511/31511.pdf ) "G" stands for 2% tolerance and 10? is resistance - but on the photos third digit/symbol is "4" as far I can see, but in the datasheet in should be R, K, M or 0.. BTW, for example, 104 makes sense - 10 to the power of 4 = 10 kOhm. Somebody please check me on this one out.

Regards,
Phil

Hello Phil and all others,

I don't know if I'm a little late.
Is there a higher resolution version of this image?

Regards

BB

karul · Post by **karul** » 29 Jan 2023, 17:15

bbkassel wrote: ↑29 Jan 2023, 14:49 Hello Phil and all others,

I don't know if I'm a little late.
Is there a higher resolution version of this image

Regards

BB

When you click on the image in the thread it will be opened in the original "biggest" resolution. Posted image by Phil is 1157 x 890. Yours is the smaller version 640 x 492.

bbkassel · Post by **bbkassel** » 29 Jan 2023, 18:17

Thank you karul,

but how can I see the larger resolution?

karul · Post by **karul** » 29 Jan 2023, 18:43

bbkassel wrote: ↑29 Jan 2023, 18:17 Thank you karul,

but how can I see the larger resolution?

First left click on the image - it will open with original - biggest resolution, then right click for the menu and you can either save it or copy, or else... Usually I open the images in new tab, then save them, if needed. If you open the menu before left click on the image to save it or copy, it will be saved with smaller resolution.

bbkassel · Post by **bbkassel** » 07 Feb 2023, 11:15

Hello everybody,
I am looking for further information and help to advance the Avalon U5 diy project. Unfortunately, this project has fallen asleep on freestompboxes.
Can anyone email me the data and hires-pictures created for this?
The only other information I found here:

https://t-sap.com/index.php?option=com_ ... &Itemid=46

Many thanks and best regards
Bernd

Avalon - U5 DI Preamp [schematic]