I have learnt a lot from this site, and would like to contribute back to the community. I have read that the site needs servers, bandwidth etc. And I hate getting banners etc that will ineveitably come with as a means to fund continued existence of the site.
How about hosting schematics, PCB patterns etc for downloading, and downloaders will be requested to pay a voluntary donation towards the upkeep of the site?
As a start, I have the following:
1. PCB layout for a 4x TDA1543 passive DAC
2. Schematic and PCB for a Sony EIAJ to I2S converter so that all thise who have CXD xxxx controller chips can use the famed TDA1541A without the need for SPDIF.
All my other work are not worth much anyway and should stay within the forum.
Comments?
How about hosting schematics, PCB patterns etc for downloading, and downloaders will be requested to pay a voluntary donation towards the upkeep of the site?
As a start, I have the following:
1. PCB layout for a 4x TDA1543 passive DAC
2. Schematic and PCB for a Sony EIAJ to I2S converter so that all thise who have CXD xxxx controller chips can use the famed TDA1541A without the need for SPDIF.
All my other work are not worth much anyway and should stay within the forum.
Comments?
My heavily modified Pionner CD player. Made all these changes:
1. All diodes changed of schocky 1N5817. Bypass the diodes with caps.
2. COmmon mode choke before the bridge rectifiers.
3. replaced all the 78xx and 79xx regulators with TL431 derived ones, with LC choke inputs and Sulzer inspired cap across cathode to ref to reduce gain as freq increase ( gives better trebles )
4. NE5534 changed to LM6172
5. removed coupling caps and muting caps at output.
6. implemented KC7 clock. Picture below shows the PCB ( with Elso's asychn reclocker not completed yet - cannot find 100 MHz crystal. I will not provide the PCB as it is not my IP to give.
Alternative output:
1. Tapped EIAJ signal from CXD1135 to connect directly to TDA1543As
2. EIAJ converter to I2S to connect to TDA1541As
3. Valve output for the TDA1541A
1. All diodes changed of schocky 1N5817. Bypass the diodes with caps.
2. COmmon mode choke before the bridge rectifiers.
3. replaced all the 78xx and 79xx regulators with TL431 derived ones, with LC choke inputs and Sulzer inspired cap across cathode to ref to reduce gain as freq increase ( gives better trebles )
4. NE5534 changed to LM6172
5. removed coupling caps and muting caps at output.
6. implemented KC7 clock. Picture below shows the PCB ( with Elso's asychn reclocker not completed yet - cannot find 100 MHz crystal. I will not provide the PCB as it is not my IP to give.
Alternative output:
1. Tapped EIAJ signal from CXD1135 to connect directly to TDA1543As
2. EIAJ converter to I2S to connect to TDA1541As
3. Valve output for the TDA1541A
Attachments
Pictures of the valve output stage:
Yes, I used common flourescent lamp ballast as chokes, and two halogen lamp transformer for the PS. One for the filament, and the other to step back up to 240Vs. The 13W ballast are cheap, 3H in value, and can take 170mA. I hope my missus do not find out that certain lights in the house no longer work not because they failed....
Yes, I used common flourescent lamp ballast as chokes, and two halogen lamp transformer for the PS. One for the filament, and the other to step back up to 240Vs. The 13W ballast are cheap, 3H in value, and can take 170mA. I hope my missus do not find out that certain lights in the house no longer work not because they failed....
Attachments
I do not intent to sell any of these stuff. If the moderators of the site thinks that no money is need to keep this site going, then I will post them for free.
If the idea of donations flies, then anyone can donate anything they want, zero if that is what they can afford. They can come back and donate money when they become millionaires.
However, they are not to be used for commercial money making schemes without my approval.
If the idea of donations flies, then anyone can donate anything they want, zero if that is what they can afford. They can come back and donate money when they become millionaires.
However, they are not to be used for commercial money making schemes without my approval.
there are some site born projects out there. Perhaps these popular circuits could be sold as kits or PCBs. I particallaly like the idea of PCBs since its so expensive to get them made and to make them...of course we all know that.
Perhaps every section of the site can come up with a circuit. Chip amps can put up a gain clone... solid state can come up with some sort of ultimate amp...digital can do a DAC....and or a cd-player...etc.
or we can always go to banner adds...they dont bother me too much.
Perhaps every section of the site can come up with a circuit. Chip amps can put up a gain clone... solid state can come up with some sort of ultimate amp...digital can do a DAC....and or a cd-player...etc.
or we can always go to banner adds...they dont bother me too much.
My Sony EIAJ format to Philips I2S converter:
This is a simple circuit. After analysing the timing diagrams of the two formats, what is actually needed is a simple delay of LRCLK by 7 BCK clocks, and for it to be inverted. Data and BCK can pass through.
The circuit consist of a VHC374 wired as a shift register – input at D1, Q1 to D2, Q2 to D3 etc. BCK is inverted to clock the 374 as it is rising edge, and then inverted again to output as I2S BCK. LRCLK is inverted by three gates and fed to D1 of 374. I added two more gates to delay LRCLK so that it is two gates delayed from when the inverted BCD clocks the shift register.
I have used up 5 of the 6 74F04 NOT gates and hence cannot buffer DATA by two NOT gates. Hence I just feed it through. Timing is not an issue as Data is clocked in the middle of BCK and hence the two gates delay of BCK is not significant. However, if you load Data by more than one gate, it might be a problem. I have loaded it with four TDA1543 with no problems.
The above works if you have 16 bits EIAJ to 16 bits I2S. I have provided taps at D5 and D3 so that you can use 18 bits and 20 bits EIAJ as well, but I have never tested it.
You can use the same scheme to convert from I2S to EIAJ. Just delay Data rather than LRCLK, and invert LRCLK.
I have the schematic and PCB in Protel 99.
For my Pioner player, it uses a CXD1135. The pin outs are:
BCK - pin 76
LRCLK - pin 80
Data - pin 78
It is the same pins for CXD1125. I do not have the datasheet and found the pins by probing for the signals, 2.11Mhz, 44.1kHz, and a random signal.
This is a simple circuit. After analysing the timing diagrams of the two formats, what is actually needed is a simple delay of LRCLK by 7 BCK clocks, and for it to be inverted. Data and BCK can pass through.
The circuit consist of a VHC374 wired as a shift register – input at D1, Q1 to D2, Q2 to D3 etc. BCK is inverted to clock the 374 as it is rising edge, and then inverted again to output as I2S BCK. LRCLK is inverted by three gates and fed to D1 of 374. I added two more gates to delay LRCLK so that it is two gates delayed from when the inverted BCD clocks the shift register.
I have used up 5 of the 6 74F04 NOT gates and hence cannot buffer DATA by two NOT gates. Hence I just feed it through. Timing is not an issue as Data is clocked in the middle of BCK and hence the two gates delay of BCK is not significant. However, if you load Data by more than one gate, it might be a problem. I have loaded it with four TDA1543 with no problems.
The above works if you have 16 bits EIAJ to 16 bits I2S. I have provided taps at D5 and D3 so that you can use 18 bits and 20 bits EIAJ as well, but I have never tested it.
You can use the same scheme to convert from I2S to EIAJ. Just delay Data rather than LRCLK, and invert LRCLK.
I have the schematic and PCB in Protel 99.
For my Pioner player, it uses a CXD1135. The pin outs are:
BCK - pin 76
LRCLK - pin 80
Data - pin 78
It is the same pins for CXD1125. I do not have the datasheet and found the pins by probing for the signals, 2.11Mhz, 44.1kHz, and a random signal.
Attachments
BTW, who is funding DIYAudio? Nothing is free in this world ( except samples ) and someone may be paying for our gain. I would like to thank them.
I would also like to thank all the contributors, and all the volunteer moderators, administrators and so forth. You guys are my hero.
How about a list of these benefactors on a page somewhere. Finally, how about setting up a paypal or whatever so that payments can be made on a voluntary basis?
I would also like to thank all the contributors, and all the volunteer moderators, administrators and so forth. You guys are my hero.
How about a list of these benefactors on a page somewhere. Finally, how about setting up a paypal or whatever so that payments can be made on a voluntary basis?
This site could probably do quite well by selling advertising space, it would require very little management unlike selling PCBs and/or kits and could also provide everyone with a good directory of parts/kit suppliers.
Of course you wouldn't want pop ads maybe space below everything currently on the front page could work.
I'm sure there will be opposition to this idea but I thought I'd put it forward anyway.
Of course you wouldn't want pop ads maybe space below everything currently on the front page could work.
I'm sure there will be opposition to this idea but I thought I'd put it forward anyway.
I like Dave's idea. Currently I spend a lot of time fabricating PCBs and buying parts. If there are people who would make some of these projects into kits, and share the profits with DIYAudio, that would be ideal. The companies willbe able to purchase parts in higher volume and pass the savings to us. E.g. a SMT cap cost 0.1 cents in reel form but we would pay 10 cents if we buy a few pieces. Ditto for semiconductors etc. Finally we save postage as we can get all from one source.
Adverts provides a service if they also provide informatin of what is available and where. Let's hope the adverts do not get agressive and SPAMS etc becomes routine!
Adverts provides a service if they also provide informatin of what is available and where. Let's hope the adverts do not get agressive and SPAMS etc becomes routine!
Someone mentioned having kits for each category.. that might be cool, or even easier would be downloadable PDF files containing step-by-step instructions on how to build say.. a tube amp. I think there are probablly a decent number of people out here that would like to build somthing like an amp, but dont know how to read schems, wire transformers.. w/e the problem may be.. it would be much easier if there were step by step instructions, plus this would only require someone to do somthin once, not have to etch a PCB and receorce parts every time someone wants a kit. tell me what you think
Hmm, a quick check shows well over 2000 members with 10 or more posts. If each of those people gave 5 bucks a month, Jason would be driving a Hummer H2 to his air conditioned server warehouse (which I would have no problem with). Realistically, anybody who gets good use out of the site could make a small donation every now and then when they feel the services here have helped them enough to warrant said donation. I have no idea how much it costs to keep this site going, but I visit the site at least a few times a week and I wouldnt mind a couple bucks a month. I dont know if this has been discussed before, but if theres a paypal address I can send money to I would gladly do so.
-Chris
-Chris
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.