![]() |
![]() |
![]() |
|
Television Standards Converters, Modulators etc Standards converters, modulators anything else for providing signals to vintage televisions. |
![]() |
|
Thread Tools |
![]() |
#21 |
Dekatron
Join Date: May 2003
Location: Edinburgh, UK.
Posts: 3,259
|
![]()
Darius sent me couple of screen shots of his converter.
Given the shape of the mask I assume these are taken from his Bush TV22. See http://www.scottpeter.pwp.blueyonder.co.uk/DAR1.jpg http://www.scottpeter.pwp.blueyonder.co.uk/DAR2.jpg Peter. |
![]() |
![]() |
#22 |
Retired Dormant Member
Join Date: Dec 2003
Location: Solingen, Germany
Posts: 727
|
![]() ![]() It is the Bush TV22, sorry for the H-lin fault. I did not find an adjustment for this in the TV22 ![]() Darius |
![]() |
![]() |
#23 |
Dekatron
Join Date: May 2003
Location: Edinburgh, UK.
Posts: 3,259
|
![]()
Hi Darius,
I haven't had my TV22 running for many years but I think the trimmer capacitor on the component strip beneath the line output stuff is your horizontal form adjustment. In TV32 they moved it onto the rear panel which is a bit more convenient. Peter |
![]() |
![]() |
#24 |
Retired Dormant Member
Join Date: Dec 2003
Location: Solingen, Germany
Posts: 727
|
![]()
Hi Peter
I'll try it out next time... tnx ![]() Darius |
![]() |
![]() |
#25 |
Dekatron
Join Date: May 2003
Location: Edinburgh, UK.
Posts: 3,259
|
![]()
Hi Darius,
Sorry, wrong info. It's the trimmer on the scan coils. Peter. |
![]() |
![]() |
#26 |
Retired Dormant Member
Join Date: Dec 2003
Location: Solingen, Germany
Posts: 727
|
![]()
Hi Peter, hi all
I found out new sensational things! I used Peter's 4046. But only the FF phase detector (PC2). I did not want to remove my LC-oscillator. The advantage of this detector is I can connect the output of the 4040 pin 14 with pin 14 of the 4046 and I put the H sync to pin 1 of the 93. So it is possible to reduce the loopfilter cap from 4,7uF to 10nF !!! ![]() The PLL reacts very fast now. I standard converted a signal from my satreceiver and it worked ok. I have ca. 2,3V DC at pin 10 of the 4046 and no ac component. Then I played a 625 VHS tape. Now the voltage at pin 10 has an AC component added caused by the jitter of the tape. Then I watched the picture in the Bush TV22 and it was exellent ![]() The standards converter acts now as a time base corrector : ![]() Peter's 625 line VHS copy from a copy looks like a DVD ![]() (except the resolution) Kind regards, Darius |
![]() |
![]() |
#27 |
Retired Dormant Member
Join Date: Dec 2003
Location: Solingen, Germany
Posts: 727
|
![]()
@Jeffrey
isn't it an easy TBC if you take the 625 video out from pin 3 of the interpolator cxl ![]() (I'll try it after my holiday) Darius |
![]() |
![]() |
#28 |
Retired Dormant Member
Join Date: Dec 2003
Location: North London, UK.
Posts: 6,168
|
![]()
Yes. But only if the oscillator used for output from the CXL is low jitter.
|
![]() |
![]() |
#29 |
Guest
Posts: n/a
|
![]()
Hi i was directed here by Peter Scott, and as i said to him i am new to this, but Darius' convertor looks great. i would be interested in obtaining the cxl chips, can anyone give me a price? if i can build this my Pye VT17CDL will live again!
many thanks John Thorn |
![]() |
#30 |
Retired Dormant Member
Join Date: Dec 2003
Location: Solingen, Germany
Posts: 727
|
![]()
Hi John
tnx for your interest. New updates are comeing soon for the converter. The interpolator is much easyer because I generated a new V-sync. and an advanced clamp for the cxl's is made. ![]() Of course I can sent you the three cxl's 35Euro including postage and tech support. ![]() Kind regards Darius my email Radio-Darius(at)t-online.de (at)=@ |
![]() |
![]() |
#31 |
Retired Dormant Member
Join Date: Dec 2003
Location: Solingen, Germany
Posts: 727
|
![]()
Hi all,
new updates on the website now. ![]() Tried to add a dscription I wrote in WORD but sorry I am not able to add it here. ![]() Darius |
![]() |
![]() |
#32 |
Dekatron
Join Date: May 2003
Location: Edinburgh, UK.
Posts: 3,259
|
![]()
Since first building Darius' converter both he and I have
been experimenting with various improvements and simplifications to the original design. http://www.scottpeter.pwp.blueyonder.../newscheme.jpg gives a schematic for a simpler version of the current design. Darius' converter basically translates three 625 lines into two 405 lines. One consequence of this is that the position of the discarded line ripples up through the frame because 625*2/3 has a remainder. An effect of this is that in fine detail such as small text etc you can see a rippling movement. Darius substantially reduces this effect by having an interpolator. The simpler proposal here uses a different approach, namely to stop the rippling by resetting the line counter at the start of each frame. The downside of this can be that there is some disturbance of the first few lines at the top of the picture. This proposal limits the line sync disturbance by synchronously resetting the line counter for the duration of one 625 line. Adding an interpolator improves the presentaion of diagonal picture content but for those who want a simpler build then this proposal gives good results and a very stable picture. http://www.scottpeter.pwp.blueyonder...newschpict.jpg The schematic is simpler is various ways. Apart from not using a third CXL for an interpolator the synchronous 74HC163 counter is used for both the clock division to obtain 2.9MHz and for the 405 line sync. The two JKs in the vertical sync path simply generate a reset pulse that is one 625 line in width. The back to back monostables (bottom right) generate the line pulses within the frame syncs. Peter. |
![]() |
![]() |
#33 |
Dekatron
Join Date: May 2003
Location: Edinburgh, UK.
Posts: 3,259
|
![]()
My photography off the screen isn't very good but
Darius sent me a photo from his TV22 showing a converted 625>405 test card from the simpler converter. This was from my converter via a 405 line VHS tape that I sent to Darius. http://www.scottpeter.pwp.blueyonder...ewschpict2.jpg |
![]() |
![]() |
#34 |
Retired Dormant Member
Join Date: Dec 2003
Location: Solingen, Germany
Posts: 727
|
![]()
http://www.your-normwandler-page.de.vu/
Good evening, I made an update for the interpolator in Page 2+5. The interpolation is made with a 50%/50% average with the delayed leaved out line and the first written line and 33% of the delayed first written line with 77% of the second written line. ![]() It sounds complicated but it isn't. You have only to put a 470 Ohms resistor between collector of Q26 and the 100uF in Blatt2. ![]() I displaced the interpolator on off switch in Blatt 5. The interpolation is perfect this way ![]() Other updates for the PLL and the antialiasing filters are comeing up as soon as possible. Kind regards Darius |
![]() |
![]() |
#35 |
Retired Dormant Member
Join Date: Dec 2003
Location: Solingen, Germany
Posts: 727
|
![]()
The antialiasing update is done.
Page 2 Darius |
![]() |
![]() |
#36 |
Retired Dormant Member
Join Date: Dec 2003
Location: Solingen, Germany
Posts: 727
|
![]()
http://www.your-normwandler-page.de.vu/
Hi, I made the PLL Update. png and tif is not possible, so you have to watch the normwandler website. (I must leran how to use the new forum.) Kind regards Darius Last edited by oldeurope; 27th Dec 2004 at 11:06 am. |
![]() |
![]() |
#37 |
Administrator
Join Date: Dec 2002
Location: Cardiff
Posts: 8,966
|
![]()
Hi Darius,
png and tif are now enabled - up to 600 by 600 pixels, and up to 100kB filesize. Let me know if those limits are reasonable (over in the Forum comments section please). |
![]() |