3rd Mar 2019, 12:58 pm | #101 |
Heptode
Join Date: Jun 2006
Location: Eindhoven, Netherlands.
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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 |
3rd Mar 2019, 1:51 pm | #102 |
Octode
Join Date: Jan 2007
Location: Dorridge, West Midlands, UK.
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Re: Hedghog standards converter
Jac
Thanks, that's puzzling! I will re-check. |
3rd Mar 2019, 2:53 pm | #103 |
Heptode
Join Date: Feb 2006
Location: Roscommon, Ireland
Posts: 732
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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
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3rd Mar 2019, 10:15 pm | #104 |
Octode
Join Date: Jan 2007
Location: Dorridge, West Midlands, UK.
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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 |
3rd Mar 2019, 11:43 pm | #105 |
Heptode
Join Date: Feb 2006
Location: Roscommon, Ireland
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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
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4th Mar 2019, 12:48 am | #106 |
Octode
Join Date: Apr 2016
Location: Ventnor, Isle of Wight, & Great Dunmow, Essex, UK.
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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 |
4th Mar 2019, 1:07 am | #107 |
Heptode
Join Date: Feb 2006
Location: Roscommon, Ireland
Posts: 732
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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
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4th Mar 2019, 1:17 am | #108 |
Nonode
Join Date: Jun 2008
Location: Coningsby, Lincolnshire, UK.
Posts: 2,820
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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! |
4th Mar 2019, 1:36 am | #109 |
Heptode
Join Date: Feb 2006
Location: Roscommon, Ireland
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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
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4th Mar 2019, 8:32 am | #110 |
Octode
Join Date: Jan 2009
Location: Falmouth, Cornwall, UK.
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Re: Hedghog standards converter
The preset is wrong way round
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Stephen _________"It`s only an old telly" ___ |
4th Mar 2019, 9:10 am | #111 |
Heptode
Join Date: Jun 2006
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Re: Hedghog standards converter
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4th Mar 2019, 11:06 am | #112 |
Heptode
Join Date: Feb 2006
Location: Roscommon, Ireland
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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
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4th Mar 2019, 11:45 am | #113 |
Octode
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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 |
4th Mar 2019, 5:17 pm | #114 |
Heptode
Join Date: Feb 2006
Location: Roscommon, Ireland
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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
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4th Mar 2019, 9:22 pm | #115 |
Heptode
Join Date: Feb 2006
Location: Roscommon, Ireland
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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
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7th Mar 2019, 11:09 am | #116 |
Octode
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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 |
7th Mar 2019, 11:39 am | #117 |
Pentode
Join Date: Oct 2003
Location: Henley on Thames, Oxfordshire, UK.
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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. |
7th Mar 2019, 10:05 pm | #118 |
Heptode
Join Date: Feb 2006
Location: Roscommon, Ireland
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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
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8th Mar 2019, 1:56 am | #119 |
Tetrode
Join Date: Jan 2019
Location: Heusenstamm, (Near Frankfurt am Main), Germany.
Posts: 59
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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 |
8th Mar 2019, 10:16 am | #120 |
Octode
Join Date: Jan 2009
Location: Falmouth, Cornwall, UK.
Posts: 1,991
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Re: Hedghog standards converter
The new software is available from franks website, it corrects some issues and is version V5
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Stephen _________"It`s only an old telly" ___ |