Finally, an affordable CD Transport: the Shigaclone story - Page 24 - diyAudio
Go Back   Home > Forums > Source & Line > Digital Source

Digital Source Digital Players and Recorders: CD , SACD , Tape, Memory Card, etc.

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 10th April 2008, 04:53 AM   #231
diyAudio Member
 
Join Date: Jun 2005
Location: Canada
Peter,

Are you using the stock magnetic puck comes with the boombox?

Thanks, A3K
  Reply With Quote
Old 10th April 2008, 05:53 AM   #232
diyAudio Member
 
Peter Daniel's Avatar
 
Join Date: Jul 2002
Location: Toronto, Canada
Send a message via AIM to Peter Daniel
Yes I do, it's not bad at all
__________________
www.audiosector.com
“Do something really well. See how much time it takes. It might be a product, a work of art, who knows? Then give it away cheaply, just because you feel that it should not cost so much, even if it took a lot of time and expensive materials to make it.” - JC
  Reply With Quote
Old 10th April 2008, 02:01 PM   #233
kevinkr is offline kevinkr  United States
diyAudio Moderator
 
kevinkr's Avatar
 
Join Date: Sep 2004
Location: Boston, Massachusetts
Blog Entries: 6
Exclamation Mixed verdict in on RCEZ32

I received my second JVC boombox last night, a model RCEZ32, that it got to me intact and was not stolen off of my doorstep is a miracle in itself.. Despite signature confirmation it was DELIVERED. My thoughtful neighbor rescued it before some roving hudlum could liberate it.

USPS- NOT TO BE TRUSTED!

Anyway on to the germane.. I do not yet have pictures of the board set or mechanism I liberated from the RCEZ32, the mechanism is identical, the boards are not.

The chip set used in the mechanism does not integrate an onboard micro-controller and hence another board is used to control playback functions in the player. The chips are respectively an LA9241, and an LC78629. Spdif output is present and accessible, and looking at the data sheets it seems clear that these chips are in the same basic family of devices used in the RCEZ31.

Substantial reverse engineering is required, however some key areas are fairly similar on the player board, things are slightly physically rearranged however. The display is driven by a separate board that incorporates the uP and many other functions. The display provides more information than the RCEZ31 as it displays both track and time. (Many functions controlled by the uP like power/standby will have to be re-implemented, while others like the analog source selection, cassette play, tuner, and digital volume control can probably be safely ignored.)

I have no idea whether or not the performance ultimately will be as good as with the EZ31 (I suspect it will be, but who knows) so unless you are looking for a challenge I would not buy one of these.

The stock boombox had quite a good level of detail, but with those tiny speakers was more than a little tinny..
__________________
"Extraordinary claims require extraordinary evidence." - Carl Sagan
  Reply With Quote
Old 10th April 2008, 02:11 PM   #234
diyAudio Member
 
Join Date: Nov 2004
Location: Utrecht
Interesting observations Kevin.
At least you discovered the RC EZ32 can be used for replacement of the mechanics. That's good to know. Mine (RC EZ31) will be delivered in a week. Signature required.
Have fun modding!
  Reply With Quote
Old 10th April 2008, 02:20 PM   #235
diyAudio Member
 
Peter Daniel's Avatar
 
Join Date: Jul 2002
Location: Toronto, Canada
Send a message via AIM to Peter Daniel
Default Re: Mixed verdict in on RCEZ32

Quote:
Originally posted by kevinkr
The chip set used in the mechanism does not integrate an onboard micro-controller and hence another board is used to control playback functions in the player. The chips are respectively an LA9241, and an LC78629.
Well, it's certainly not bad news at all; that unit is closer to Shigaraki than EZ31. Shigaraki also uses separate chipset to handle display functions, as pictured here: http://www.audiostereo.pl/zalaczniki/905391_1.jpg
__________________
www.audiosector.com
“Do something really well. See how much time it takes. It might be a product, a work of art, who knows? Then give it away cheaply, just because you feel that it should not cost so much, even if it took a lot of time and expensive materials to make it.” - JC
  Reply With Quote
Old 10th April 2008, 02:26 PM   #236
johnm is offline johnm  United Kingdom
diyAudio Member
 
johnm's Avatar
 
Join Date: Sep 2003
Location: Hampshire
My EZ31B arrived this morning, and I've dismantled the poor old boombox and am surrounded by parts!!! Felt a bit weird taking apart a brand new unit - Mum thought I was nuts haha!

Anyway, have the relevant parts connected up and ready to go - am currently using the stock transformer/PSU board, and the larger PSU/'mother' board until the parts arrive for a dedicated supply. Also makes judging the effects of the new supply vs standard a possibility.

Problem is I hastily snipped off ALL the three wires contained in the terminal block just above the figure-8 power input socket. The two black AC leads go direct to the transformer, then two yellow wires goto the AC+ and AC- points marked on the small PSU board.

When connecting power I'm not getting anything out of the system - no CD turning, no LED on. I think that when a figure 8 lead is plugged in, it pushes up a switch which 'tells' the unit not to use battery power. I ** THINK ** this creates a link between the B+ on the PSU board, and DC+ on same board. I'm fairly certain I need to add a wire link between these two points.

Could someone please comfirm this before I ruin my new mechanism?!?

Many thanks!

- John
  Reply With Quote
Old 10th April 2008, 02:41 PM   #237
kevinkr is offline kevinkr  United States
diyAudio Moderator
 
kevinkr's Avatar
 
Join Date: Sep 2004
Location: Boston, Massachusetts
Blog Entries: 6
Hi John,
The power switch you describe correctly. On mine if you connect the orange and yellow leads together it will work. (Assuming your power supply is the same as the one used in the RCEZ32.)

Acquiring one of these units has been an unpleasant experience to say the least, my faith in the integrity of our local postal carriers is 0 at this point. My wife thought it was a little strange that I would buy and dismantle a perfectly good boombox, and I had to explain why I need one of these specific models. Guess I was getting a bit too angsty over this, now that I have one I should get "better."

Hi Peter,
I actually meant to mention the Shigaraki had two boards in it, and in fact mentioned that to my friend Nick in an email this morning. It looks viable, just more complex than versions built using the EZ31..

Any details anyone has on the EZ32, schematics in particular would be highly appreciated.
__________________
"Extraordinary claims require extraordinary evidence." - Carl Sagan
  Reply With Quote
Old 10th April 2008, 02:51 PM   #238
johnm is offline johnm  United Kingdom
diyAudio Member
 
johnm's Avatar
 
Join Date: Sep 2003
Location: Hampshire
Thanks Kevin you put my mind at reast

On the UK version it's the red + black wires together to the battery + and DC+ in on the PSU board when the mains leads is out.

With mains lead plugged in it's the yellow and black to B+ and DC+ on the PSU board.

Glad your unit finally arrived. If it makes you feel better I was getting angsty about mine arriving as well and e-mailed the poor staff at Bennetts online 3 times

Now the fun (hopefully) begins once I've soldered B+ and DC+ together on that board.

Cheers,

- John
  Reply With Quote
Old 10th April 2008, 03:12 PM   #239
johnm is offline johnm  United Kingdom
diyAudio Member
 
johnm's Avatar
 
Join Date: Sep 2003
Location: Hampshire
It's ALIVVVEEEEE AAAAhahahahahahahaaaaa!

Ahem.



Whew thank gawd for that - once that lead between DC+ and B+ was connected all powered up fine. No pyrotechnics thankfully!

So far it seems pretty good - nice solid bass in particular, quite organic sounding, but a little dull at present. To be expected after only 5mins running in time and no mods as yet! Can't wait to get started on the PSU.

One question, what is the reasoning behind having those two 75-ohm resistors on the digial output? I am currently using mine without these and it appears fine - my DPA PDM One - series 2 had no trouble locking on.

- John


Update: After only 20minutes it's starting to really show potential already. Sound has opened up considerably, and the top end is improving. This looks promising
  Reply With Quote
Old 10th April 2008, 04:02 PM   #240
kevinkr is offline kevinkr  United States
diyAudio Moderator
 
kevinkr's Avatar
 
Join Date: Sep 2004
Location: Boston, Massachusetts
Blog Entries: 6
Quote:
Originally posted by johnm
It's ALIVVVEEEEE AAAAhahahahahahahaaaaa!

Ahem.



<snip>

One question, what is the reasoning behind having those two 75-ohm resistors on the digial output? I am currently using mine without these and it appears fine - my DPA PDM One - series 2 had no trouble locking on.

- John


Update: After only 20minutes it's starting to really show potential already. Sound has opened up considerably, and the top end is
improving. This looks promising
Hi John,
The reason for those resistors is for level shifting and to match the spif output port to the characteristic impedance of the interconnect cable you are using which is theoretically 75 ohms. I selected values of 243 and 110 ohms for mine which results in a 75 ohm source and should the output voltage in an acceptable range for standard spdif assuming pp swing on the output of the port of around 3.0 - 3.5Vpp - if its higher than this I may need to recalculate the values. (243 ohm from chip connected to 110 resistor which is connected to ground. Spdif out from point between the two resistors - standard voltage divider. Spdif is normally in the range of 1Vpp.)
__________________
"Extraordinary claims require extraordinary evidence." - Carl Sagan
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



New To Site? Need Help?

All times are GMT. The time now is 06:40 PM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright ©1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2