UK Vintage Radio Repair and Restoration Powered By Google Custom Search Vintage Radio and TV Service Data

Go Back   UK Vintage Radio Repair and Restoration Discussion Forum > Specific Vintage Equipment > Television Standards Converters, Modulators etc

Notices

Television Standards Converters, Modulators etc Standards converters, modulators anything else for providing signals to vintage televisions.

Closed Thread
 
Thread Tools
Old 3rd Mar 2019, 12:58 pm   #101
Jac
Heptode
 
Jac's Avatar
 
Join Date: Jun 2006
Location: Eindhoven, Netherlands.
Posts: 640
Default Re: Hedghog standards converter

Chris,

After your post, I checked and my Hedghog is (at channel 1) at 41.5 and 45.0 MHz.
Both with previous and the latest program.
Hope this helps...

Jac
Jac is offline  
Old 3rd Mar 2019, 1:51 pm   #102
chriswood1900
Octode
 
Join Date: Jan 2007
Location: Dorridge, West Midlands, UK.
Posts: 1,472
Default Re: Hedghog standards converter

Jac
Thanks, that's puzzling! I will re-check.
chriswood1900 is online now  
Old 3rd Mar 2019, 2:53 pm   #103
FRANK.C
Heptode
 
FRANK.C's Avatar
 
Join Date: Feb 2006
Location: Roscommon, Ireland
Posts: 729
Default Re: Hedghog standards converter

Hi Chris
I haven't got an analyser to check. But I have checked through the way the FPGA programmes the modulator chips on channel 1 and everything appears OK there.
You should be getting 41.5 MHz/45 MHz.
Let us know how you get on.

Frank
__________________
FRANK.C is offline  
Old 3rd Mar 2019, 10:15 pm   #104
chriswood1900
Octode
 
Join Date: Jan 2007
Location: Dorridge, West Midlands, UK.
Posts: 1,472
Default Re: Hedghog standards converter

Thanks Frank, perhaps I have an errant modulator chip, I enclose a picture of the output from the Analyser.
Centre frequency 41.5Mhz and the marker on the Vision at 45.5Mhz the levels are a bit out as its a 50ohm Analyser unit with a 75ohm adaptor. I, will have a look over the data sheet next week while I'm away working, it probably won't be for a week or so before I can get back on it.
Chris
Attached Thumbnails
Click image for larger version

Name:	Scan.jpg
Views:	155
Size:	88.4 KB
ID:	179378  
chriswood1900 is online now  
Old 3rd Mar 2019, 11:43 pm   #105
FRANK.C
Heptode
 
FRANK.C's Avatar
 
Join Date: Feb 2006
Location: Roscommon, Ireland
Posts: 729
Default Re: Hedghog standards converter

Hi Chris
500KHz is a nice round number I was thinking along the lines of a stuck control bit in the modulator chip.
The divider division ratio control bits for 45 and 45.5 MHz is shown below. There is only 1 bit in the difference.
45 MHz = "101101000000"
45.5 MHz = "101101100000"

However Chanel 3 vision is
56.75 MHz = "011100011000"

If the same bit was stuck high you should be getting
57.75 MHz = "011100111000"

Even so I still think it is most likely a fault in the modulator chip.


Frank
__________________
FRANK.C is offline  
Old 4th Mar 2019, 12:48 am   #106
1100 man
Octode
 
1100 man's Avatar
 
Join Date: Apr 2016
Location: Ventnor, Isle of Wight, & Great Dunmow, Essex, UK.
Posts: 1,377
Default Re: Hedghog standards converter

I fitted a modulator chip into IC5 position but it doesn't seem to do much. Granted I don't have a 405 TV here and only the world's most useless scope. I would have expected to see 45Mhz on the frequency counter connected to the output though.

There's 5V on all the pins there should be and no volts on the pins that should be grounded. The chip is not getting hot. I can't see anything on the SDA or SCL lines going to the chip- I would have expected to see something on the scope.

All the dip switches are 'on' and there is video going in to pin 9

I'll wait until the end of the week when I will have access to a 405 TV to test it properly and a better scope.

In the meantime, I'll start on HH No2 which will allow me to make comparisons.

Cheers
Nick
1100 man is online now  
Old 4th Mar 2019, 1:07 am   #107
FRANK.C
Heptode
 
FRANK.C's Avatar
 
Join Date: Feb 2006
Location: Roscommon, Ireland
Posts: 729
Default Re: Hedghog standards converter

Hi Nick
The DIP switches SW8 A ans SW8 B needs to be in the 'Off' position. In the 'On' position the modulators are off.

There is very little activity on the SDA and SCL lines. The only time you have any chance of seeing anything on a scope is when the channel is changed or when either modulator is turned on or off.
The activity then will be brief.

Frank
__________________
FRANK.C is offline  
Old 4th Mar 2019, 1:17 am   #108
Lloyd 1985
Nonode
 
Lloyd 1985's Avatar
 
Join Date: Jun 2008
Location: Coningsby, Lincolnshire, UK.
Posts: 2,814
Default Re: Hedghog standards converter

Mine are so close to being finished now, modulator chips turned up on Friday, but I still haven't fitted them yet! All the rest of the SMD stuff is in place, and all the switches and sockets are fitted too. I even screwed the boards into their cases, even though they will have to come out again. I'm just waiting for the FPGA's and the header sockets to arrive, then I can get programming and see if they are going to work!

Regards,
Lloyd.

PS; lets see if anyone spots the little error I made!
Attached Thumbnails
Click image for larger version

Name:	IMG_6316.jpg
Views:	173
Size:	126.8 KB
ID:	179382   Click image for larger version

Name:	IMG_6317.jpg
Views:	180
Size:	95.7 KB
ID:	179383   Click image for larger version

Name:	IMG_6318.jpg
Views:	169
Size:	68.2 KB
ID:	179384  
Lloyd 1985 is offline  
Old 4th Mar 2019, 1:36 am   #109
FRANK.C
Heptode
 
FRANK.C's Avatar
 
Join Date: Feb 2006
Location: Roscommon, Ireland
Posts: 729
Default Re: Hedghog standards converter

Hi Lloyd
They are looking good. You are getting very close.


One word of warning. Don't attempt to remove or insert the FPGA board while the Hedghog PCB is screwed to the case. It puts a lot of pressure on the surface mounted components that are located near the screw holes and can crack them.

Frank
__________________
FRANK.C is offline  
Old 4th Mar 2019, 8:32 am   #110
Freya
Octode
 
Freya's Avatar
 
Join Date: Jan 2009
Location: Falmouth, Cornwall, UK.
Posts: 1,981
Default Re: Hedghog standards converter

The preset is wrong way round
__________________
Stephen
_________"It`s only an old telly" ___
Freya is offline  
Old 4th Mar 2019, 9:10 am   #111
Jac
Heptode
 
Jac's Avatar
 
Join Date: Jun 2006
Location: Eindhoven, Netherlands.
Posts: 640
Default Re: Hedghog standards converter

Quote:
Originally Posted by 1100 man View Post
I would have expected to see 45Mhz on the frequency counter connected to the output though.
Nick,

The output is too small for most frequency counters.
I tried this with my Hedghog on 3 different counters and none was able to display the carrier frequency.

Jac
Jac is offline  
Old 4th Mar 2019, 11:06 am   #112
FRANK.C
Heptode
 
FRANK.C's Avatar
 
Join Date: Feb 2006
Location: Roscommon, Ireland
Posts: 729
Default Re: Hedghog standards converter

Hi Chris
Jeffrey on the Golborne Vintage Radio Forum checked his Hedghog and found the same problem. That prompted me to check the older files as the firmware in his Hedghog is an older version and sure enough the programming of the vision modulator on channel 1 in that version is incorrect. That's something I had totally forgot about.

So if you have programmed it with an older version of the firmware programming it with the latest version should solve it.

Frank
__________________
FRANK.C is offline  
Old 4th Mar 2019, 11:45 am   #113
chriswood1900
Octode
 
Join Date: Jan 2007
Location: Dorridge, West Midlands, UK.
Posts: 1,472
Default Re: Hedghog standards converter

Thanks Frank
I thought I had updated to the latest but I will recheck the version I am using but it won't be for a few days.
Regards
Chris
chriswood1900 is online now  
Old 4th Mar 2019, 5:17 pm   #114
FRANK.C
Heptode
 
FRANK.C's Avatar
 
Join Date: Feb 2006
Location: Roscommon, Ireland
Posts: 729
Default Re: Hedghog standards converter

Hi Chris
I have been looking through the files to try and work out where it was corrected and I believe it was in version V04.
I will be soon updating the firmware to V05 and it defiantly will be correct in that.

Frank
__________________
FRANK.C is offline  
Old 4th Mar 2019, 9:22 pm   #115
FRANK.C
Heptode
 
FRANK.C's Avatar
 
Join Date: Feb 2006
Location: Roscommon, Ireland
Posts: 729
Default Re: Hedghog standards converter

Firmware version V05 can now be downloaded from the webpage.
This rectifies slight misalignment of pedestal and non pedestal video. Enforced blanking before broad pulses has been removed.
Added captions to the test card. Firmware version can now be viewed on screen by switching from grey scale to test card.

Frank
__________________
FRANK.C is offline  
Old 7th Mar 2019, 11:09 am   #116
chriswood1900
Octode
 
Join Date: Jan 2007
Location: Dorridge, West Midlands, UK.
Posts: 1,472
Default Re: Hedghog standards converter

Hi Frank
Success I have uploaded V5 software and it is working as it should, I think I had V3.03 previously.
With regard to the 2 audio presets is there any procedure for correctly setting them up?
Thanks for the support.
Chris
Attached Thumbnails
Click image for larger version

Name:	IMG_2262.jpg
Views:	136
Size:	71.3 KB
ID:	179529  
chriswood1900 is online now  
Old 7th Mar 2019, 11:39 am   #117
radiomarktv
Pentode
 
Join Date: Oct 2003
Location: Henley on Thames, Oxfordshire, UK.
Posts: 242
Default Re: Hedghog standards converter

Hi Frank,

Just a big thank you for the Hedghog standards converter. The two converters I've built have been running for a month now with great success. Both now upgraded to V5.
Do you have any more PCB's available as I wish to build another converter into my video rack along side my BBC broadcast camera.

Mark.
radiomarktv is offline  
Old 7th Mar 2019, 10:05 pm   #118
FRANK.C
Heptode
 
FRANK.C's Avatar
 
Join Date: Feb 2006
Location: Roscommon, Ireland
Posts: 729
Default Re: Hedghog standards converter

Chris
That's great thanks for letting us know.

SW8A and SW8B switch off the vision and audio modulators so they can be viewed individually on a scope to aid setting up the audio carrier level.

As far as I understand the audio carrier should be 6dB down on peak white.
What I do is hook up the scope with a 75R load to the RF out. The video out can be used to trigger the scope. Then switch Hedghog to display the grey scale and switch off the audio modulator. View the video RF noting the level of peak white. Then switch off the video modulator and switch on the audio modulator and adjust the audio carrier pot for 6dB down.
Adjust audio gain control to suit the audio level coming from the equipment supplying Hedghog.

Mark
Thank you. it's good to hear that your Hedghog's are working well.
I have plenty of the PCB's left. So just send me a PM letting me know how many you need.

Frank
__________________
FRANK.C is offline  
Old 8th Mar 2019, 1:56 am   #119
Semir_DE
Tetrode
 
Semir_DE's Avatar
 
Join Date: Jan 2019
Location: Heusenstamm, (Near Frankfurt am Main), Germany.
Posts: 59
Default Re: Hedghog standards converter

Hi Everyone,

this is just to let you know that the first Hedghog in Germany is now operational. I had programmed the FPGA last night and had also finished the PCB. Soldering the TVP5150 was quite a challenge though but I managed.

After running first tests my impression is WOW! or in German I would say "Affengeil!" . The image quality and performance is absolutely superb! I am very impressed! Frank C. has done a fantastic job in creating this little device! Thank You Sir!

As I am planning to use a totally different case I have not added any switches and only the necessary components for testing. I have made the following changes:

- Used low profile 2x14 pin headers for the FPGA board, so it would rest a little lower than in the original design. This, however, necessitated removing the power connector from the FPGA board.

- Omitted the 7805 regulator. I am powering the unit from an old Blackberry mobile phone charger via a micro USB jack. This worked very well. The unit consumes about 250mA, so most chargers should be fine as they usually can supply at least 500mA. I also checked the Hedghogs performance to voltage variations and between 4.8V and 5.2V I could not see any significant performance degradation.

- I will use BNC connectors for the Video I/O and RCA Connectors for the Audio. All Signal connectors will be mounted in the back of the case.

Attached I have a few images of my Hedghog PCB. I will post the final image when I have installed it in its case.

Semir
Attached Thumbnails
Click image for larger version

Name:	Semirs_Hedghog_First_Image.jpg
Views:	174
Size:	75.0 KB
ID:	179570   Click image for larger version

Name:	Semirs_Hedghog_VG1000_Testcard.jpg
Views:	171
Size:	74.0 KB
ID:	179571   Click image for larger version

Name:	Semirs_Hedghog_First_Video_Helene_Fischer16by9_DVD.jpg
Views:	171
Size:	80.9 KB
ID:	179572   Click image for larger version

Name:	Semirs_Hedghog_DVD_Avengers.jpg
Views:	177
Size:	64.3 KB
ID:	179573  
Semir_DE is offline  
Old 8th Mar 2019, 10:16 am   #120
Freya
Octode
 
Freya's Avatar
 
Join Date: Jan 2009
Location: Falmouth, Cornwall, UK.
Posts: 1,981
Default Re: Hedghog standards converter

The new software is available from franks website, it corrects some issues and is version V5
__________________
Stephen
_________"It`s only an old telly" ___
Freya is offline  
Closed Thread

Thread Tools



All times are GMT +1. The time now is 10:14 am.


All information and advice on this forum is subject to the WARNING AND DISCLAIMER located at https://www.vintage-radio.net/rules.html.
Failure to heed this warning may result in death or serious injury to yourself and/or others.


Powered by vBulletin®
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Copyright ©2002 - 2023, Paul Stenning.