![]() |
![]() |
![]() |
|
Television Standards Converters, Modulators etc Standards converters, modulators anything else for providing signals to vintage televisions. |
![]() |
|
Thread Tools |
![]() |
#1 |
Retired Dormant Member
Join Date: Nov 2005
Posts: 40
|
![]()
Anyone who is contemplating buiding Darius's Standards Convertor and is put off by the apparent difficulty is sourcing the CXL5508, or MSM7403, CCD delay line IC's may find this useful.
After many fruitless enquiries to try to obtain CXL's I gave up and looked for an alternative. This effort produced the LC8992, from Sanyo, which seems to be a near perfect equivalent for the CXL, except it's need for a slightly higher dc supply rail (9v). It's not a surface mount either, for those who dont want eye strain. Although officially listed as discontinued by Sanyo there still seems to be stock out there. I've just ordered 6 from Grandata at 70p each, although I think I've cleared them out for now. However, a quick check shows it's available elsewhere too. The datasheet is here if you need it http://www.datasheetarchive.com Hope this helps someone. Graham. |
![]() |
![]() |
#2 |
Retired Dormant Member
Join Date: Dec 2003
Location: Solingen, Germany
Posts: 727
|
![]()
Good morning Graham,
I am not sure with this duty cycle det. at pin 8. Maybe it is a PLL and causes problems with the clock frequency switching. But at this very low cost you must try it out. For the interpolator it is ok, look at the cxl5506 it has double clock frequency and gives you full resolution. Kind regards Darius |
![]() |
![]() |
#3 |
Retired Dormant Member
Join Date: Nov 2005
Posts: 40
|
![]()
Hi Darius,
Thanks for the reply. As you say, at that price it is certainly worth a try ![]() I have tried all my UK chip suppliers and none of them can supply any of the CXL chips (of any number). I've tried US suppliers too but they all have $500 or $250 minimum order values per item! I have yet to try the Philips part number because I dont have an account with a Philips parts supplier anymore since moving into the office equipment repair field instead of TV/Video. The MSM7403A (which I believe is an OKI device, but they have no data) seems as hard to obtain and an additional problem is that a datasheet seems impossible too! There seems no problem at all obtaining any of the other logic to me, but I don't mind surface mount so it gives me more options. Regards, Graham. |
![]() |
![]() |
#4 |
Retired Dormant Member
Join Date: Dec 2003
Location: Solingen, Germany
Posts: 727
|
![]()
Hi Graham,
It is not a big problem to adapt the smd to dil with a DIL socket. Look at the pic. Some of the ccd's have an internal PLL because of the duty cycle or to double tripple or quadruble the input clock frequency. I have ccd's in stock, the cxl5508m 15 Euros and the cxl5506m 25 Euros. I ordered them as replacements for vcr's. Kind regards Darius |
![]() |
![]() |
#5 |
Retired Dormant Member
Join Date: Nov 2005
Posts: 40
|
![]()
Hi Darius,
Thanks for your reply. It's not smd that's a problem (I have smd prototyping boards), it's just getting the chips at all! I have now found your archived thread relating to full resolution with the CXL5506. I'm assuming you increased the clock speed and adjusted the dividers for the MKIII version then? Also I think you added the switchable colour trap. I don't think I've seen a schematic for that MKIII version, is one available? Currently I'm working to the MKII schematic of the 26/10/05. Today I have found one UK supplier who lists the CXL5506 as being available, but, of course when asked, has no stock. However, they are going to get back to me to let me know if a)they can get them, and b) whether the minimum order will be 10, 25, 50 or 100! I said I'd go for 10 if neccessary. Thanks for the offer to supply chips. If I continue to fail to find a source of CXL's, and the LC8992 won't do the job, I may take you up on your offer. At this rate I may be buying old VCR's on ebay just for 3 chips ![]() Regards, Graham. |
![]() |
![]() |
#6 |
Moderator
Join Date: Jan 2003
Location: Ipswich, Suffolk, IP4, UK.
Posts: 20,637
|
![]()
Dial Electronics www.dialelec.com stock the CXL5508P at £1.62 and CXL5508M (no price given) and have no minimum order charge.
Graham. |
![]() |
![]() |
#7 |
Retired Dormant Member
Join Date: Nov 2005
Posts: 40
|
![]()
Thanks Graham, but been there and tried that! They seem to be defunct as a company, it was all too good to be true!
Regards, Graham. |
![]() |
![]() |
#8 | |
Retired Dormant Member
Join Date: Dec 2003
Location: Solingen, Germany
Posts: 727
|
![]() Quote:
The difference to the MKIII is the cxl's invert the signals and have an other signal level. The input stage is changed. The clock circuit is not much different, the divide by two after the divide by three (pos.12h) is replaced by a 4046 to get a 50% duty cycle after dividing by three. The two 40103 are replaced by one 4059, HCT of course. I drawed the schematic for the analog part of the MKIII (in the style like the schematics for the MKI) and I started a discription for it with Peter Scott. It is not finished. I must finish it because with the time I'll forget what I have done ![]() Kind regards Darius |
|
![]() |
![]() |
#9 | |
Retired Dormant Member
Join Date: Nov 2005
Posts: 40
|
![]() Quote:
![]() Thanks again for looking though Graham...much appreciated. Regards, Graham |
|
![]() |
![]() |
#10 | |
Nonode
Join Date: May 2007
Location: Redruth, Cornwall, UK.
Posts: 2,443
|
![]() Quote:
Just wondering if you managed to use the LC8992 ics successfully in place of the CXL5508 and if so did you need any modifications to the circuit? As you point out the CXL ics are becoming very difficult/expensive to locate. Regards Symon. |
|
![]() |
![]() |
#11 |
Dekatron
Join Date: Feb 2005
Location: St.Ippolyts, Hitchin, Hertfordshire QRA IO91UW
Posts: 3,513
|
![]()
Symon,
GDtv has retired from the forum, so you will not get a reply from him. Cheers Sean
__________________
Engineers make things work and have spare bits when finished |
![]() |
![]() |
#12 | |
Nonode
Join Date: May 2007
Location: Redruth, Cornwall, UK.
Posts: 2,443
|
![]() Quote:
Hello Sean. Thanks for letting me know that. Maybe other forum members have had some experience trying to use the LC8992 in place of the CXL5508. I am currently communicating with Darius with regard to his excellent standards converter and modulator. These are very interesting/challenging circuits that I am in the process of building. I will of course post pictures of the completed project. Regards Symon. |
|
![]() |
![]() |
#13 |
Nonode
Join Date: May 2007
Location: Redruth, Cornwall, UK.
Posts: 2,443
|
![]()
Hello again.
I thought that I would just let other members know that I finally managed to obtain some CXL5508M ics for the Darius Standards converter. I like others, had previously spent many fruitless hours trying to find these elusive parts. I had been dealing with a chap, John Harper, on eBay (jhcomp25) and by chance asked if could get hold of these parts. He put himself out and within a few days I had them. Now the only thing is there's a minimum order quantity of ten units. I purchased this number at a very reasonable price of £6.60 each. I would imagine this price is subject to variation depending on the availability. John Harper can be contacted at jhdisATaol.com. (AT=@) or by telephone 01543 417471, or by Fax 01543 419001. I hope this is helpful to other members who are contemplating building this excellent project and may I point out that I have no financial interest in his business. Best regards Symon McCabe. |
![]() |