|
Anthony Good
Has anyone attempted to troubleshoot this issue recently? This evening I placed a grounded piece of PC board on top of the LM380 and also tried 0.001uF caps between pins 14 & 3 and 7 & 8, to no avail.
I may just bypass the LM380 audio amp and place an outboard 386 audio amp board in to drive the speaker…. 73 Goody K3NG |
|
Goody, The guys ar HF Signals were saying that these are faulty LM380s. A replacement works without the interference. I will attempt this on my own board and report back with week. On Mon, Sep 12, 2022, 5:28 AM Anthony Good <anthony.good@...> wrote: Has anyone attempted to troubleshoot this issue recently?? This evening I placed a grounded piece of PC board on top of the LM380 and also tried 0.001uF caps between pins 14 & 3 and 7 & 8, to no avail. |
|
Anthony Good
开云体育I just installed a new LM380 with a socket and it didn’t solve the Wi-Fi interference issue for me. ?It did however improve the audio quality, especially at low volumes.I say “new” LM380, but it has a 1993 date code on it….
|
开云体育Anthony - from what I have seen on the Wi-Fi interference, the best solution is to disable the w/f & use an ethernet cable. Gerry Sherman Sent by the Thunderbird On 2022-09-12 02:05, Anthony Good
wrote:
I just installed a new LM380 with a socket and it didn’t solve the Wi-Fi interference issue for me. ?It did however improve the audio quality, especially at low volumes. |
|
Anthony Good
开云体育Agreed; I’ve been running off of Ethernet. ?I do all my development work via SSH and VNC. ?Networking is a must! :-)
|
|
Haven't had much time to debug a thing.. but happened to have the sbitx on with wifi? .. the screen went blank and it was drawing about? 423 mA.. when the wifi noise came on it was drawing about 30 - 40? mA less. A clue? who knows, but if I find the time to finally jump into the game I want to remember this point.?
|
|
I inserted a sheet of single sided copper clad board (.030") between the Rpi
and the Mezzanine board.? With it grounded? to the audio band it worked fine, no more clicks. The Wifi is on the Rpi board and being in the box it hears wifi weakly and assumes full power TX and the audio is right next (less than an inch) away.? So its not surprising. What might help is having the interface board on a short stand off or even at a right angle to get it further away......? THen its over the relays and LPF also may be problematic good.. External is better for range as well.? For those so inclined its possible (Warning: SMT ahead) to add a connector and use an external antenna. Allison ------------------ Please use the forum, offline and private will go to bit bucket. |
|
Raj,
I use wireless mouse and KB with the Rpi, works well. Also requires no standing power from the Rpi if the basic power source is weak. The only nuisance is some keyboards fall? to a sleep state and you can miss keypresses. Allison ------------------ Please use the forum, offline and private will go to bit bucket. |
|
I tapped the screen to wake it up and it made a QSO with a YC1
toggle quoted message
Show quoted text
On 12/10/2022 7:49 PM, ajparent1/kb1gmx wrote:
Raj, |
|
Goody,
Putting a grounded board on topp of the 380 is not useful. It has to be under it as the WiFi comes off the Rpi. Also ground leads at 2.4ghz have to be very short! If not they are antennas.? Also the wolfson en-dec could also be doing picking it up. Allison ------------------ Please use the forum, offline and private will go to bit bucket. |
|
The pick up is not there on earphones. It is coming from the LM380 die.? Btw, the production guys told me something interesting : certain LM380s don't have the wifi interference at all! - f On Thu, Oct 13, 2022 at 12:06 AM ajparent1/kb1gmx <kb1gmx@...> wrote: Goody, |
|
Anthony Good
开云体育Yea, I know. ?I tested it and it didn’t work. :-)
|
N0YWB
Raj vu2zap