Qui c’è una presentazione in italiano sull’efficienza degli schemi di modulazione più popolari tra i radioamatori ed altre amenità sopra il rapporto segnale/rumore e cose espresse in dB.
Buona lettura!
AEA DSP-2232 complete manual and undocumented jumpers
Unfortunately this beautiful TNC is not well documented (at least not as his brother PK-232). I’ve been able to acquire the complete manual with schematics (albeit something does not add up) and with some tinkering I discovered the use of most of the undocumented jumpers on the boards.
- JPA1, JPA2: bypass LP filters
- R166, R164: used to have 0V on PIN 20 of U41, U39
- JP11, JP12: bypass compressor
- JPT1, JPT2, JPR1, JPR2: jumper on (jumper off if you have DSP-1232, K1 must be installed too)
- JP1, JP2 on the daughter board: mystery
Pioneer RT-909 restoration
I made up a PDF of the supergood thread on audiokarma.org on restoring Pioneer RT-909 Reel-to-reel tape deck:
Thread: Restoring a Pioneer RT-909 Reel-to-Reel
PDF: Restoring a Pioneer RT-909 Reel-to-Reel in PDF
Good luck!
Correct sequence to change configuration on Cisco Ether Channels
There we go again, I just keep forgettin’ things that every time are obvious. Say you have to change a configuration on a Portchannel interface. How to do it? Since the physical ports must have the same configuration of the Portchannel interface for the Ether Channel to come up there must be a sequence. And ideed there is.
- Change configuration on the physical interfaces in the group
- Change, finally, the configuration on the port channel interface
Long live and prosper.
I have to have this post: unsupported Cisco SFP/GBIC
Everytime it’s all over the internet and I still keep forgetting how to convince a Cisco switch not to complain about 3rd party SFP/GBICs.
So here I am: how to use a couple of unsupported, undocumented, beautiful commands to make a Cisco almost like a non-Cisco SFP/GBIC:
no errdisable detect cause gbic-invalid
service unsupported-transceiver
That’s it. It’ll work if you have IOS 12.2(25)SE and above (so it seems: verification needed).
Using 24 Vdc in Mikrotik CCR series
CCR series routers from Mikrotik are (more or less) powerful devices intended for enterprises… A part from marketing they don’t have redundant power neither DC power option: only 230 Vac.
I needed to power them with 24 Vdc, I tampered, checked, measured and easily found a place in the PCB. Here’s a close-up:
And that’s a larger view of the internals of a Mikrotik CCR series router:
Happy DC powering!
Hello world!
Hi everyone, I’m a communication engineer and my job is about networking but electronics has always been a great passion as well as being a radio amateur. This blog is about things that I learn/experiment/resolve
The post title fits very well: it’s the first classic simple program that everyone writes in a new computer programming language that is being learnt. Not me. Even if it’s not a computer language but a networking device I end up always in trying to do something just slightly complex than the basics. This happens not only when I need to code something but in almost every other technical endeavour.
That thing ditches me. And these are my stories of how I emerged from every single ditch I dug 🙂
P.S. ‘Affossati’ is the italian word for “ditched“.