Hi all,
just chatting with someone about tape loading and I remembered that I have a small device that shows you whether the iPod / tapedeck etc connected to your 6128 is at the correct volume for succesful loading. It's small, cheap and pretty useful (if you happen to like loading tapes to your 6128).
Is there any interest in a batch of these, or should I toss it back into the box of random circuits I just fished it out of?
Bryce.
It would indeed be nice!
It would be nice as a project to make up... give me more practice with my soldering iron (usually means breaking more things tho!)
Quote from: Chinnery on 17:19, 26 February 18
It would be nice as a project to make up... give me more practice with my soldering iron (usually means breaking more things tho!)
Do you mean as a kit or just publish the schematics?
Bryce.
It depends on how many people are interested. I know buying "1 of" parts for a kit can become a bit expensive, but if not enough people are interested then that's something I'm willing to do - make boards etc from the eagles / gerbers and source the parts.
I suppose what would also be of interest to me is what are the components doing. I'm more of a code monkey than a hardware guru, but would love to learn a bit more on the hardware side... and projects like this where I can see the results in an area of interest would be great.
It's a very simple circuit. Easily understood.
If I can get 10 people interested I'll make a batch. I need to check what the parts cost to work out the price.
Bryce.
Quote from: Bryce on 22:16, 26 February 18
It's a very simple circuit. Easily understood.
If I can get 10 people interested I'll make a batch. I need to check what the parts cost to work out the price.
Bryce.
Count me in Bryce! ;)
[size=78%] [/size]
I'll buy one, too - had to transfer Amdrum tapes from PC to a real cassette recently (external datacorder)... would have been easier with the tape cable directly into the CPC, and level indicator.
Count me in for one too!
Me too
I want one, please! :)
I think a gadget like this sounds very useful. I could be interested too.
Ok, that's enough interest to pull it back out of the box and start a layout :)
Edit: Just messing about laying out a new Prototype. A quick survey for those who stated interest: The device obviously needs power and there's no power on the Cassette port, soooo.... What's preferable? A flylead to connect it to the 5V power or run it off a 9V battery (it would run for a very very long time from a 9V battery).
Also, who would want to build it themselves and how many would want a built device?
Bryce.
If is posible I prefer a built device. Battery seems more practical to me.
I'd prefer the assembled version, too. ;)
I must admit a kit would be more fun, running from 5v, but am sure I could adapt the kit to my needs... may make the project more challenging :)
Ok, I've decided to make it 3V to 10V, so you can connect it to whatever you want and power it how you want. I will build them for those who want and you can let me know how you'd like it powered. @Chinnery (http://www.cpcwiki.eu/forum/index.php?action=profile;u=2434): A kit is no problem either. It's all thru-hole parts and if you are completely hamfisted at soldering I can include sockets.
Bryce.
Quote from: Bryce on 08:39, 01 March 18
@Chinnery (http://www.cpcwiki.eu/forum/index.php?action=profile;u=2434): A kit is no problem either. It's all thru-hole parts and if you are completely hamfisted at soldering I can include sockets.
I was promoted from hamfisted to udder-fingers solderer not too long ago ;)
However, I've plenty of sockets here so that's fine!
Congratulations on the promotion :D
Bryce.
A bit late to the party, but I would like to have one too :) It still load tapes from time to time and the device would put an end to my childhood nightmares. Moreover, it can be particularly useful for the 6128+ :D .
One for me, please? Battery seems preferable... Also, a cool analog VU meter or something :D
Quote from: Gryzor on 19:19, 03 March 18
One for me, please? Battery seems preferable... Also, a cool analog VU meter or something :D
Yeah but these are expensive these days $£€ 8)
That's the cheapest I could find :laugh:
https://www.ebay.com/itm/VU-Meter-ANALOG-RECORDING-sticker-decal-4-X-8-/280449743000 (https://www.ebay.com/itm/VU-Meter-ANALOG-RECORDING-sticker-decal-4-X-8-/280449743000)
This one is actually real ;)
https://www.ebay.com/itm/40mm-x-40mm-Analogue-VU-Meter-500uA-1-25-pcs-/282846205515 (https://www.ebay.com/itm/40mm-x-40mm-Analogue-VU-Meter-500uA-1-25-pcs-/282846205515)
That's not a bad price, he can add LEDs, too :D
Unfortunately an analogue display would require a completely different circuit, so an analogue version won't be possible.
Bryce.
I'll vote for battery powered too. And pre-built :)
There's actually no difference between the 5V and 9V versions, so I think I'll just supply them all with the 9V battery version with the comment "This can be powered fropm the CPC 5V intead if required".
I did a quick layout last night and I'll make a prototype (excuse to play with my newly built CNC PCB router :) ) as soon as I have time.
Bryce.
Any news ? :)
I've been away for ages and have a huge backlog of repairs to get through, so no, nothing further has been done at the moment.
Bryce.
Quote from: Bryce on 10:47, 19 April 18
I've been away for ages and have a huge backlog of repairs to get through, so no, nothing further has been done at the moment.
Bryce.
No problem, i just wanted to have news ;)
How is this one doing btw?
It's not, but as soon as I have finished building the Joystick testers I'll get back to it.
Bryce.
Now that i finally found the time to hook up my external tape player, this would come very handy !
Now that I'm stuck at home, it may be a good time to actually do this project :D
Bryce.
Would the level indicator work in the case of recording a file from the PC soundcard to tape?
It would work with any sound source connected to the CPCs Tape input socket.
Bryce.
Quote from: Bryce on 15:28, 18 May 20
It would work with any sound source connected to the CPCs Tape input socket.
Well then, count me in for one as well, if you're still taking interests.
Bryce,
My first post here - I've just purchased a non working CPC6128 from EBay - Hopefully it should arrive sometime next week.
More years ago then I care to remember I owned a "fully loaded" CPC464 with green screen monitor. I dont recall any tape loading errors with the CPC464 internal tape drive - how sensitive / fussy is the CPC6128's tape interface circuit? I recall my first "computer" a ZX81 being a real hit or miss affair - yes lost so many hours having to retype code after a failed save to tape...
As your going to so much effort to design / building / testing / shipping PCB's I wonder if it would not be beneficial to add a couple of band-pass filters to improve the robustness of the tape interface circuit - not sure what coding format Amstrad used on the tape interface, but suspect its some form of FSK modulation... I would imagine a coupe of bandpass filters set around the 1 / 0 tones would make a huge difference to the reliability of the interface... I would be happy to help with the schematic / PCB layout if you wanted... we could added the level meter after the bandpass filters to give a really decent indication of level...
The PCB could be powered from the 5V or 12V... inserted in the power leads from the monitor...
Is there any decent information on the CPC's Tape interface / modulation scheme? What would be great is test software that generates test tones over the tape interface.. it really should not be that hard to do... the tape port seems to be connected directly to the 8255... this does leave many possibility to improve the interface.
When my unit arrives I can investigate the interface - but I don't currently even own a tape cassette player / cassette tapes...
I'll also purchase a CPC464 when I clean unit comes up to probe its internal tape section - it will be strange to own one again after so many years...
A bandpass filter would improve the reliability, I even have it on my list of trials. However, the volume seems to be the thing that most people battle with, which is why I looked at making a level indicator in the first place. The 464 doesn't have this issue as the tapedeck has fixed volume.
As far as schematics / layouts are concerned, I think I already had them finished when I (temporarily) abandoned this project. My plan was to power it all from a 9V battery for several reasons: It doesn't need to be permanently powered, a battery introduces no additional noise to the signal and there are already many other CPC expansions taking power from the 5V rail.
If you think the ZX81 was hit and miss, try loading a tape on an Oric 1 :D
Bryce.
Now your just being flash :D I was too poor to own an Oric1 :'( - you really have to ask yourself HOW anything could have a worst tape interface then the ZX81!!!
They managed it by messing up the firmware, if you install the Oric Atmos Firmware it's almost as reliable as a ZX81 :D
I like the Avatar pic, is that to compliment my Max Headroom theme?
Bryce.
Arh yes - Dear Amanda Payes - my first "Love" the reason I watched Max Headroom ;D - wonder how the series has fared the test of time!
I used to digitize the video image with my CPC video digitizer card (was it from John Morrison? - then upgraded to a Romco or some such)... Max actually came out quite well - maybe due to his limited palette and resolution...
You can have Max, I'll keep Amanda! :D
A TAPE LEVEL INDICATOR? 8) :o
Wow, you guys are really developing HIGHTECH here, aren't you? 8)
No wonder development of this kind of sophisticated equipment takes YEARS!
Quote from: VintageAdvantage on 18:40, 20 May 20
A TAPE LEVEL INDICATOR? 8) :o
Wow, you guys are really developing HIGHTECH here, aren't you? 8)
No wonder development of this kind of sophisticated equipment takes YEARS!
Wow I think someone thinks they can do better? Go ahead make my day
Quote from: tjohnson on 20:21, 20 May 20
Wow I think someone thinks they can do better? Go ahead make my day
Hold your johnson uhmm horses - all cool ;D
Quote from: VintageAdvantage on 20:55, 20 May 20
Hold your johnson uhmm horses - all cool ;D
Cheers Uncle Sam, horses held.
Quote from: VintageAdvantage on 18:40, 20 May 20
A TAPE LEVEL INDICATOR? 8) :o
Wow, you guys are really developing HIGHTECH here, aren't you? 8)
Indeed, we have our CPC's arranged in a Mini CPC super Cluster with custom developed node to node RS232 networking maxed out at 19200 baud to power the simulation tools...
Quote from: VintageAdvantage on 18:40, 20 May 20
No wonder development of this kind of sophisticated equipment takes YEARS!
Something of very great concern to the whole team, we have been exploring the possibility of overclock our CPU's to 8MHz to reduce the simulation times... we might need to resort to water cooling - we are however concerned about the upper clock limit of the CPC's ASIC... working at the forefront of technology is just so fraught with challenges!!!
We are dedicating the full engineering mindset of the collective, but have no fear - a working level meter is near!
Quote from: VintageAdvantage on 18:40, 20 May 20
A TAPE LEVEL INDICATOR? 8) :o
Wow, you guys are really developing HIGHTECH here, aren't you? 8)
No wonder development of this kind of sophisticated equipment takes YEARS!
Why does it have to be something High-Tech? Lo-Tech things can be extremely useful to users too. Should we stop making spoons because they are not sophisticated enough?
Bryce.
Quote from: Bryce on 15:13, 21 May 20
Why does it have to be something High-Tech? Lo-Tech things can be extremely useful to users too. Should we stop making spoons because they are not sophisticated enough?
Bryce.
I took the original post from VintageAdvantage as just jest :) no negative intent..
BTW - this level meter from EBay looks interesting, could be powered from the Monitor 12V output.
https://www.ebay.com/itm/New-32-LED-Level-Indicator-VU-Meter-Music-Sound-Audio-Display-Analyzer/382481146148? (https://www.ebay.com/itm/New-32-LED-Level-Indicator-VU-Meter-Music-Sound-Audio-Display-Analyzer/382481146148?)
Yeah, but I'd prefer my own single PCB layout with the sockets and other components together. Also, it has way too many LED's. The device only needs maybe 7 LED's: 3x Red, one green in the middle and 3x Red on the other side. So you know where to hit. The entire device can be much smaller than that.
Bryce.
That sounds much more useful having a level meter that gives a target level to hit.
Quote from: Bryce on 16:45, 21 May 20
Yeah, but I'd prefer my own single PCB layout with the sockets and other components together. Also, it has way too many LED's. The device only needs maybe 7 LED's: 3x Red, one green in the middle and 3x Red on the other side. So you know where to hit. The entire device can be much smaller than that.
Bryce.
If time is an issue, then this PCB could be made to work:-
https://www.ebay.co.uk/itm/Sale-1-PC-New-Suite-LM3915-Audio-DIY-Kit-Level-Indicator-Electronic-Production/123198886313? (https://www.ebay.co.uk/itm/Sale-1-PC-New-Suite-LM3915-Audio-DIY-Kit-Level-Indicator-Electronic-Production/123198886313?)
The pair of RED LED's could be positioned in the center of the LED array to to indicate the Target Playback level - with the LM3915 put into Dot mode (theres a wire link jumper position on the PCB - Pin 9 to select Dot mode). If the number of LEDS offends your sensibilities then you dont have to populate them all :)
The Gain trim pot can be set so that the displays mid section indicates optimal tape replay level - you would have to live with the counter intuitive RED LED's indicating the correct level.
Can be powered from a 9V battery...
That's pretty much what my circuit would do, but with the correct footprint for the CPC tape socket, a bandpass filter and the level (instead of that pot) would be fixed for the correct CPC level.
Bryce.
Compared to other vintage machines, the tape interface of the CPC is pretty good. So I am surprised that such a device is needed at all.
The 464 tape circuitry is well designed and at fixed levels. This design is only intended for the 6128 where there is no filtering or anything, just a direct connection from the socket to the 8255.
Bryce.