best cheap/free scores 1.1

[mikay786]

Re: best cheap/free scores 1.1

Thanks, How come one input is female and one a male?

The cable I linked to above Is 3.5mm to dual male xlr, wil the this work or will I need one with one female and male?

I've got the fuses just removed to have a look.

[Compgeke]

Re: best cheap/free scores 1.1

You only need the 3.5mm to male. The male and female is usually used to hook the male for input (yellow) and output that same signal over female (magenta) to another amp or whatnot rather than using a bunch of runs from the source.

Another reason would be for some odd setup that uses the inverse connections although that's fairly uncommon, usually would be doing something like hooking a microphone right into the amp bypassing a mixer or anything.

[mikay786]

Re: best cheap/free scores 1.1

Ta, could this amp be used as a power amp for a home theatre system powering a passive sub? I've just got a 7.1 hk amp and can use the b&o sub with it.

So from hk pre out out to this power amp.

[Compgeke]

Re: best cheap/free scores 1.1

That'd work. Big thing I'd do first is give it a good cleaning and get some output fuses. Do initial testing with sacrificial speakers and check dc offset.

As for fuses, I don't see any markings stating what they are and a quick search doesn't pull anything up. Being a 500W amp I'd take a guess and say it originally used 250V, 2.5A fuses. I'd do more research and check to see if you can find what the originals were.

[mikay786]

Re: best cheap/free scores 1.1

That'd work. Big thing I'd do first is give it a good cleaning and get some output fuses. Do initial testing with sacrificial speakers and check dc offset.

As for fuses, I don't see any markings stating what they are and a quick search doesn't pull anything up. Being a 500W amp I'd take a guess and say it originally used 250V, 2.5A fuses. I'd do more research and check to see if you can find what the originals were.

It says T8A next to the fuse slots and original ones in there are T 8Amp Ceramic Fuses. There is one normal fuse in there too but that looks like a replacement and the should again be a ceramic one.

[mikay786]

Re: best cheap/free scores 1.1

So measured DC offset and getting 33mv on right channel and -20mv on left channel

Is this within tolerance or is the 33mv too high?

[Compgeke]

Re: best cheap/free scores 1.1

20 and 33 are fine, I'd be worried if it was above 50 myself. If it were above 100 you'd have to worry about it tripping into protection and sounding like crap.

[mikay786]

Re: best cheap/free scores 1.1

Having some trouble getting a signal into this amp. Not getting any sound from speakers aside from the gentle buzz on power up. I think its something to do with how I'm connecting it rather than a problem with amp.

So this is how I have it wired up

3.5mm out from PC
to XLR Right Amp input and XLR Left Amp input

One speaker on right channel

----------------------------------------------------------------

Reading the pinout on the amp XLR inputs it says Pin 1 = Ground & Pin 3 = Live

----------------------------------------------------------------

Doing a continuity test pin out on the 3.5mm to Dual XLR is

• Red XLR Pin 2 = Tip of 3.5mm Left / Pin 3 & 1 = Ground or base of 3.5mm
  
• Black XLR Pin 2 = Middle of 3.5mm Right / Pin 3 & 1 = Ground or base of 3.5mm

Is that how it should be or something up here?

[mikay786]

Re: best cheap/free scores 1.1

The 3.5mm XLR connector wiring is

pin 3 + 1 + shield are bridged ground

[SteveNielsen]

Re: best cheap/free scores 1.1

Check the left channel.

[mikay786]

Re: best cheap/free scores 1.1

Yep was the way it was wired, from a quick google apparently some british amp manufacturers wired up their XLR connectors differently than normal.

So wired up the 3.5mm to dual xlr so right and left channels to pin 3 on each connector and ground to pin 1 (bridged with the shield) pin2 blank

and is working.

BUT

The right channel (which has the higher DC offset) seems to have static. When i mute audio from source and turn volume up on amp there is static cracly noise coming through speaker.

[SteveNielsen]

Re: best cheap/free scores 1.1

Do you have a schematic for it? Leaky caps in the RT channel output section can cause that symptom and account for the higher DC offset voltage at the speaker output.

[mikay786]

Re: best cheap/free scores 1.1

I might be going loopy but it sounds like its picking up something like interference and the static has a beat to it? It does it for a few seconds then stops, then does it again and stops etc

Could a dirty pot cause it?

I think I do have a schematic, see attached

[mikay786]

Re: best cheap/free scores 1.1

DC Offset rises to and levels off at +40mv, left channel is negative -20mv

[mikay786]

Re: best cheap/free scores 1.1

Ok the right channel volume control pot is definitely scratchy and it feels gritty too. Not as smooth as the other. Up until about half way its just scratchy once I go past half way I get the static playing through speakers.

Tried some contact cleaner followed by switch cleaner but no luck.

[ratdude747]

Re: best cheap/free scores 1.1

MEGASCORE!

Found a 2TB WD Mybook for mac for $3... and so far it works great. Had the original power and USB 2.0 cables with it too.

Still testing it out... I found it at a goodwill in the rich part of Indianapolis (Carmel, where I'm working this week). My guess was some apple fan probably upgraded to a USB 3.0/Thunderbolt version. Didn't even format it... it's full of apple time machine backups from 2012 through 2013, belonged to a mac owner by the name of Chad.

Assuming all is good, this very well may be my best goodwill score of all time. $3. WTF?

[stj]

Re: best cheap/free scores 1.1

the white ones? - premium!!

[momaka]

Re: best cheap/free scores 1.1

Good score RD. I decided to check the online stores on some of the GW stores in my area, and one of them seems to have two 500 GB Western Digital "Routers" for $8. They come with the power adapters too. I might go to the closest one near my house just to see what they have there out of curiosity.

[ratdude747]

Re: best cheap/free scores 1.1

I swung by after work, when they opened for the day. It was on the stocking cart. Saw something with USB and Power coming off it, grabbed it for a look (expecting some POS or the like) and saw it was a WD mybook. Looked up the model number, showed as mybook for mac of some sort. Got to my hotel room, hooked it to my laptop, and what do ya know, legit 2TB. Seems to run OK too... but if I want SMART info, I'll have to crack it open

edit- it is one of these: http://www.microcenter.com/product/3..._wdbaag0020hch

[Dan81]

Re: best cheap/free scores 1.1

Got some more scores:

ASUS N6600GT 128MB - pretty much dead. Recapped and it still doesn't show anything. Also,any motherboard would not POST with this card. It's AGP btw.

Gigabyte GA-8IE2004 - this one just needed LOTS (and I really mean LOTS) of cleaning. Came with an wimpy CM heatsink and a utter garbage labeled Cooler Master fan,which turned out to be T&T (Thieves and Thugs Co. INC,a division of HongKongFlyApart LLC.). I actually replaced the Celeron (which wasn't worth much either) and the HSF with a beefy Titan TTC-W6TB/825 cooler and a Pentium 4 1.7GHz. Older core but I guess it will do until I find a 2.8GHz Northwood. One question though,does Delta make Titan's fans?

Codegen 300X1 300W - Okay. Before you go and say "Codegen isn't good,throw away" this one is actually one of their better built PSUs (https://www.badcaps.net/forum/attach...4&d=1329244001) and after all,it was cheap! I gotta find a new fan for it though. If it works fine and sounds alright (this one is almost silent) then it goes in there. If not,then I'll just wire the fan to 12V.

Also,I fixed my old FX5500 I had around. Bad bios chip. Just used a thin staple to remove the pins of the BIOS from a donor board (Palit FX5200 w/o DVI,128M),and then used lots of rosin and soldered the new BIOS chip. Took me 20 minutes or so,because the iron has a sightly blunt tip,but it still did the job. Plugged it in on the test bench (above Gigabyte board,P4 1.7GHz,128MB RAM,8GB HDD w/ Win98SE,"450W" SunPro built Delux PSU.),and it greeted me with the usual nVidia BIOS message - "MSI (Personal Cinema) FX5200 BIOS - PAL" - and then,the usual POST screen - the chipset of the board is 845E,btw.

I'm pretty much thinking of moving the Codegen to a new case with rocker switch.
However,there is a problem - this PSU has a PCB (PFC I guess) on the female AC socket and the usual male AC plug doesn't. I was thinking - I have the bottom part of a Sumvision PSU,which it not only has room for the plugs,but for an ON/OFF switch too.
My question is,I also have a male plug w/ PCB,extracted from a Deer.

What do you think,should I have two PCBs for the plugs in there? Or is that risky?