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-   Television Standards Converters, Modulators etc (https://www.vintage-radio.net/forum/forumdisplay.php?f=95)
-   -   Hedghog standards converter (https://www.vintage-radio.net/forum/showthread.php?t=153198)

FRANK.C 16th Jan 2019 8:30 pm

Hedghog standards converter
 
I have been ask a few times if I would supply complete Hedghog's or kits but I am not in a position to do that.
I can only supply the PCB's which are in the Offered section of this Forum.

Forum member Freya has told me that he is willing to supply complete Hedghog's.
So anyone wanting a complete one can get in contact with him.

Frank

dragonser 17th Jan 2019 12:28 pm

Re: Hedghog standards converter
 
Hi,
thank you both for answering the question I had though about asking but hadn't got around to it !

FRANK.C 17th Jan 2019 8:44 pm

Re: Hedghog standards converter
 
Hi Peter
Thanks for replying, don't hesitate to ask any question about it.

I am really happy that Stephen has decided to provide this service as there is many looking for it.
Stephen was one of the first to build a Hedghog.

Frank

line sync 21st Jan 2019 8:46 pm

Re: Hedghog standards converter
 
I took delivery of a hedghog converter today built by forum member freya and I have to say I`m very impressed with it.
I love how versatile this unit is by the use of the many toggle switches on the front panel.
The unit comes in a neat little case and has a built in modulator.
I would like to say thank you to frank for designing this great little unit.

Robin

FRANK.C 21st Jan 2019 9:24 pm

Re: Hedghog standards converter
 
Thanks Robin, I am glad you like it. I am sure Stephen has made great job of it.

A lot of credit has to go to Jeffrey Borinsky Forum member ppppenguin on the Golborne Vintage Radio Forum. He introduced me to FPGA's and very generously thought me a lot about them.
Prior to that I avoided FPGA's like the plague and would never have considered using one mainly because I didn't understand what they were. Using a FPGA was a turning point in this project and made it into what it is today. Without Jeffrey's help it would have been a very different converter.

If anyone is considering designing a converter the thread about it on the Golborne Forum would be a good read. Not for my input but solely for Jeffrey's. He has given a huge amount of information and advice on that thread for anyone wanting to design one.

Frank

beltinge bore 26th Jan 2019 4:02 pm

Re: Hedghog standards converter
 
I also have a Heghog which I badgered young Stephen"Freya" into building for me.
It is great.The only thing that would improve it IMHO is a"Made in Cornwall" Sticker!
Regards Steve.

FRANK.C 27th Jan 2019 12:08 pm

Re: Hedghog standards converter
 
Hi Steve
I am glad you like it. Stephen makes a great job of them.

Frank

Silvered_Mica 2nd Feb 2019 6:11 pm

Re: Hedghog standards converter
 
Hello all,
How critical is the 14.31818 meg crystal, load capacitance, tolerance and frequency stability?

FRANK.C 2nd Feb 2019 7:13 pm

Re: Hedghog standards converter
 
Hi Silvered_Mica
Load capacitance = 18pF
Tolerance should be 50 ppm or better.
A crystal like this one should be fine.

Frank

FRANK.C 3rd Feb 2019 6:51 pm

Re: Hedghog standards converter
 
1 Attachment(s)
I updated the program so the converter can now convert from 16:9 to both 4:3 and 5:4 as well as converting from 4:3 to 4:3 and 5:4. To facilitate this the top two positions of the tone switch are now used to switch between 4:3 and 16:9 input. The selection of 400 Hz or 1KHz tone is on the DIP switch SW8-D. The new program file and legends to suit can be downloaded from the Hedghog web page.

Frank

Panrock 5th Feb 2019 7:09 pm

Re: Hedghog standards converter
 
I've just noticed the spelling - without a central E!
Why is this?

Steve

FRANK.C 5th Feb 2019 7:38 pm

Re: Hedghog standards converter
 
Hi Steve
It was a spelling mistake I made on the first lot of PCB's I got made. I though why not? and decided to keep it that way. :)


Frank

ianm 6th Feb 2019 10:09 am

Re: Hedghog standards converter
 
The spelling of Hedghog immediately puts me in mind of the town Bridgwater, in Somerset. Works well for me!

FRANK.C 6th Feb 2019 2:17 pm

Re: Hedghog standards converter
 
One consequence is that if doing a internet search it helps to filter out the unwanted results:D

Frank

Graham G3ZVT 6th Feb 2019 11:43 pm

Re: Hedghog standards converter
 
Quote:

Originally Posted by FRANK.C (Post 1117729)
It was a spelling mistake I made on the first lot of PCB's I got made. I though why not? and decided to keep it that way.

We admire you for admitting that! At least a Google search with that spelling isn't swamped by spiny mammals.

I am still curious, is there any particular connection with the project to the prickly critter?

Brigham 7th Feb 2019 10:14 am

Re: Hedghog standards converter
 
The front panel's a bit 'prickly'.

FRANK.C 7th Feb 2019 8:27 pm

Re: Hedghog standards converter
 
Hi Graham
No particular connection but as Brigham has said the toggle switches do look just a little bit spiky:)

Frank

FRANK.C 7th Feb 2019 8:55 pm

Re: Aspect ratio
 
1 Attachment(s)
Quote:

Originally Posted by 1100 man (Post 1118320)
Does the H.Hog zoom in and just loose the edges or stretch the picture vertically and give tall thin people?

I've just been playing with an HDMI to composite box from Ebay and displaying the output on a Thorn 1500.
I can only get 16:9 from my laptop which is displayed, as you would expect, with bands top & bottom.

A further problem comes when viewing something that was originally in 4:3 (eg. vintage TV adds from Youtube). You then get bands at the sides as well. What I need to be able to do is to zoom in to get rid of the border all round.

Is there any hardware or software that allows this to be done?

Hi Nick
The latest version of the Hedghog firmware does aspect ratio conversions of
4:3 => 4:3
4:3 => 5:4
16:9 => 4:3
16:9 => 5:3
It does this by cropping the beginning and ends of each line by the appropriate amount.
I have uploaded a picture of a 16:9 input with each of the above conversions applied to it.

Frank

Panrock 8th Feb 2019 9:38 pm

Re: Hedghog standards converter
 
What's the RF output level of one of these units?

Steve

Freya 8th Feb 2019 9:59 pm

Re: Hedghog standards converter
 
It measures 74dB with respect to 1uV on all the ones I have produced which is practically the same as the Aurora I think.
Happily runs 3 sets no problem

Panrock 8th Feb 2019 10:12 pm

Re: Hedghog standards converter
 
Thanks. If you mean 74dBuV (5mV), that's a little less than the Aurora's 76dBuV (6.3mV) but still a good level to have.

Steve

1100 man 9th Feb 2019 12:25 pm

Re: Hedghog standards converter
 
Hi Frank,
I've decided to take the plunge & have a go at building one of these. I'm sure it would be far more sensible to buy a built one from Stephen but where's the fun in sensible? ;D

There are a couple of anomalies in the component list. These are C37 & C41. Both are shown as 10nf on the circuit but the part number on the component list shows that for 10 mfd.

Looking at the circuit, C37 couples the video signal into the modulator IC. Should both of these components be 10n or 10mfd?

Many thanks
Nick

Freya 9th Feb 2019 4:38 pm

Re: Hedghog standards converter
 
C37 & C41 are both 10nF

Argus25 10th Feb 2019 12:47 pm

Re: Hedghog standards converter
 
Freya,

I think those Hedghog converters look really great (very nice job). Can you give a rough indication of the price of a completed unit ?

Freya 10th Feb 2019 12:58 pm

Re: Hedghog standards converter
 
Only price by PM, which I will send.

1100 man 10th Feb 2019 3:10 pm

Re: Hedghog standards converter
 
Quote:

Originally Posted by Freya (Post 1118934)
C37 & C41 are both 10nF

Many thanks!

So far, Farnell can supply almost everything and in small quantities too. SMD resistors & caps can be ordered in 10's for not much money. They can supply all the semiconductors including the IC's except the two modulator chips and the FPGA board.
I'm still working through the component list but so far, so good!

Strangely, Farnell list all the LM7805 variants as 'no longer made'! which was a surprise. I should have some somewhere though. The one component I can do from stock is the 1N4001 as it's a real one with legs!

When it comes to programming the FPGA, will the Altera software run under Linux? I don't have access to a Windows machine- in fact the last Windows I used was W98! I'm on shaky ground anyway when it comes to using computers but I do have a PC running a current version of Lubuntu.

Many thanks
Nick

TonyDuell 10th Feb 2019 3:21 pm

Re: Hedghog standards converter
 
I have not looked at this project, so if the 7805 is used in some very odd way that makes the exact part critical then I apologise.


Quote:

Originally Posted by 1100 man (Post 1119193)
Strangely, Farnell list all the LM7805 variants as 'no longer made'! which was a surprise. I should have some somewhere though. The one component I can do from stock is the 1N4001 as it's a real one with legs!

It's just a 5V, 1A fixed voltage regulator, surely. Farnell do plenty of them from other manufacturers. Do a search for '7805' on that site, for example :


https://uk.farnell.com/texas-instrum...323602?st=7805

1100 man 10th Feb 2019 3:58 pm

Re: Hedghog standards converter
 
Yes, of course,you are quite correct- it was just me being stupid! :dunce: I never thought of looking for one with a different prefix! I must have been playing with valve TV's for too long!
This project is at the other extreme:- I can't even see half the components!

All the best
Nick

FRANK.C 10th Feb 2019 4:33 pm

Re: Hedghog standards converter
 
Hi Nick
There was mistakes on the original documents on the web page I believe they have all been corrected now. So any one starting the project should download a fresh copy of them.
If any mistakes are found on a fresh copy please let me know.

As Tony has said and 5V 1A linear regulator with the correct pin layout should be fine.

There is a Linux version of the Altera software but I have not tried it. I used the windows version.

Hi Steve
Hedghog uses two MC44BS373CA modulators as does the Aurora. So the output should be fairly close there may be differences in the way that the outputs from the two modulators are combined which could account for any difference in level.

Frank

Lloyd 1985 10th Feb 2019 6:38 pm

Re: Hedghog standards converter
 
I’ve made a start on my 2, so far so good! I’ve put all except 2 values of resistor down, as I didn’t have them, and started on the caps. More stuff arriving tomorrow hopefully, from Mouser, I got the rest of the caps and some of the silicon from them, I’ve only ordered 1 FPGA so far, and it won’t even be posted until after the 14th, all the Chinese eBay sellers seem to be on holiday until then! I still need to order a few bits, mainly switches, the toggles are quite pricey! I might go for alternatives from RS, since I’ll be getting the 16 position hex switches from there.

Regards
Lloyd

Freya 10th Feb 2019 6:59 pm

Re: Hedghog standards converter
 
Hi Lloyd,

If you wanted to keep it channel 1 until your hex switch arrives, just bridge the outer pad to the nearest of the four.

Radio_Dave 10th Feb 2019 8:48 pm

Re: Hedghog standards converter
 
I'm hoping to finish my Hedghog tomorrow:). I notice the rotary hex switch shows 0 to 9 and then A to F. Does channel 1 start at 1 on the switch and then A is for channel 10 etc?

Thanks
David

1100 man 10th Feb 2019 8:51 pm

Re: Hedghog standards converter
 
Somewhere, in the last couple of days, on one of the various HH threads on one of the three Forums, I've seen the part number for the new, slim line case. Also for the vertical preset for the audio level adjustment.
I don't seem to be able to find them again! Could someone point me in the right direction?

Many thanks
Nick

Freya 10th Feb 2019 9:07 pm

Re: Hedghog standards converter
 
HI David,
That is correct.


Nick,

Farnell
108249 for 5k
108252 for 50k

TBH the gain control really only needs the initial setting then its fine.

1520397 slim case

FRANK.C 10th Feb 2019 11:33 pm

Re: Hedghog standards converter
 
1 Attachment(s)
Quote:

Originally Posted by Lloyd 1985 (Post 1119271)
the toggles are quite pricey!

Hi Lloyd
The switches are one of the more expensive components. I know a constructor that used different phono sockets but he said he wouldn't do it again as it was more trouble than it was worth. It may be same with the switches.

I just took delivery on Friday of one of these lots. They are the 2 position type. I couldn't find any 3 position types on the same site. I have tested one in a PCB and the foot print is correct. The quality is not as good as the ones listed in the parts list but are probably OK. The actuator is longer than the ones listed in the parts list.
Photo below shows from top to bottom

RS Stock No. 734-7132 a 3 position type. It has a longer actuator than the one from AliExpress.
The one from AliExpress.
A MULTICOMP 1MS3T2B4M7RE which is in the parts list.

Frank

1100 man 11th Feb 2019 12:18 am

Re: Hedghog standards converter
 
Thanks for the part number information, Stephen.

The RS stock number for the 3 position toggle switch is 734-7132 £2.65 each
The RS Stock number for the 2 position toggle switch is 734-7107 £1.58 each

I have decided to stick with the original, larger case for my unit. It will give me greater flexibility if I want to do any modifications in the future. I have also decided to use chassis mount phono sockets & power socket. I think this will be more robust for the usage the unit will get. They are also simpler to source.

I have now compiled an order for all the parts in the most economical way. The only things coming from RS are the toggle switches & the hex switch. Everything else is from Farnell baring the two modulator IC's & the FPGA.

It took a while to sort out the 14 pin headers. By far the cheapest option was to buy 2x 50 way ones from Farnell for £1.10 each. I can cut these down to 14 pin ones.

Is there a recommended supplier for the FPGA dev board & 'blaster', or does one just have to take pot luck on Ebay?

Many thanks
Nick

Radio_Dave 11th Feb 2019 12:38 am

Re: Hedghog standards converter
 
The 3 position multicomp switches are only £1.16 each at CPC;)

I also saved some money by buying only white phono sockets from ebay (£3.59 for 20) and added coloured circles to the front and back panel legends.

David

FRANK.C 11th Feb 2019 12:56 am

Re: Hedghog standards converter
 
Hi Nick
They will work fine but the actuator on the 734-7107 is shorter.

A 3 position toggle switch 734-7132 and
a 2 position toggle switch 734-7078 would have the same length actuator.

The 734-7107 is identical to the MULTICOMP 1MS1T2B4M7RE in the parts list but I don't believe there is a RS PRO version of the 3 position MULTICOMP 1MS3T2B4M7RE.

It is so long ago since I got my Blaster that I don't know who I got it from but I think it was a UK seller. I take pot luck buying the FPGA boards.

Frank

FRANK.C 11th Feb 2019 1:01 am

Re: Hedghog standards converter
 
Quote:

Originally Posted by Radio_Dave (Post 1119387)
The 3 position multicomp switches are only £1.16 each at CPC

Hi Dave
That's a great find. The 2 position switches are a good price too.

Frank

Lloyd 1985 11th Feb 2019 1:04 am

Re: Hedghog standards converter
 
Good spot David! That’s better than the ones I’d found on RS, they were made by TE Connectivity, part no’s 710-9612 for the 3 pos, and 710-9750 for the 2 pos. I’d actually forgotten about CPC! I’ll be sticking to the design as best I can, stands more chance of working then!

Nick, I just picked the cheapest of the FPGA boards that came with the USB blaster, mine came to £13.06. I need a second one, but I’ll get both Hedghog’s working with just one to begin with, then buy another without the blaster.

Regards
Lloyd

1100 man 11th Feb 2019 11:01 am

Re: Hedghog standards converter
 
Thanks Frank & Lloyd for the information. I never gave the actuator length on the switch a thought, but it seems they are all different!

I had also forgotten about CPC for some reason but it would seem that for on line orders delivered to your normal delivery address, there is no small order charge. That assumes I've read the terms correctly!

I think it has taken longer to source all the parts than it will to actually build the thing!!

I find it amazing to compare the technology and construction in the HH to the valve telly's that we will be using it with! Worlds apart!

All the best
Nick

Radio_Dave 11th Feb 2019 12:23 pm

Re: Hedghog standards converter
 
Apart from giving it a good wash in IPA I've just finished my first Hedghog. Where do I set the four DIP switches? Is there anything else I need to know before I power it up?

Regards
David

FRANK.C 11th Feb 2019 1:43 pm

Re: Hedghog standards converter
 
Hi Dave
Any switch position will not be the cause of magic smoke to be lost. So after checking the soldering etc. Just power up and see what happens.:)

To start off probably best to have all the DIP switches in the off position.
I would set it to test card as a first test.

Frank

FRANK.C 11th Feb 2019 1:51 pm

Re: Hedghog standards converter
 
Hi Nick
I only knew about the actuator length because I got caught out with it.

Hi Lloyd
I didn't spot the TE Connectivity switches on RS they are a better price that the Multicomp ones.

It is a great help when there are so many building the same project what one misses another will spot.
Anyone find a good price for the Hex switch?

Frank

gramofiend 11th Feb 2019 2:00 pm

Re: Hedghog standards converter
 
Quote:

Originally Posted by Freya (Post 1119147)
Only price by PM, which I will send.

Hi I'm just in the throws of starting a refurbisment of a Decca projector tv model 131 and realised, when finished, it will need a 405 line signal.
Could you please tell me how much you would charge to supply one Hedghog ready made?

regards

Mike.

ps am sending a PM.

Radio_Dave 12th Feb 2019 7:23 pm

Re: Hedghog standards converter
 
2 Attachment(s)
I took me a while to diagnose a faulty modulator chip but once changed it works perfectly and I have to say I'm amazed at how good it is. Thanks Frank you're a genius!

I've attached a modified version of the front panel below. I squeezed the writing for the toggle switches to make it look a little less cluttered and added channel numbers to the selector switch;).

Regards
David

Freya 12th Feb 2019 7:32 pm

Re: Hedghog standards converter
 
Very nice, I especially like the colour ring on the video socket.
Out of interest what were the symptoms of the faulty modulator chip ?

FRANK.C 12th Feb 2019 8:07 pm

Re: Hedghog standards converter
 
Hi David
Glad you like it and it is working well for you. A faulty modulator chip can be hard to diagnose. I had two. One was short across the power lines. It did not show a short on a multimeter but when left powered up for a few seconds it was easily found with a index finger. The other was producing interference on the picture which looked like ignition interference.

I like your front panel particularly the channel numbers. Thanks for uploading it.

Frank

Radio_Dave 12th Feb 2019 8:09 pm

Re: Hedghog standards converter
 
1 Attachment(s)
Quote:

Originally Posted by Freya (Post 1119944)
Very nice, I especially like the colour ring on the video socket.

I've attached another file with colour rings around the phono sockets. I used this because I penny pinched by buying only a pack white phono sockets:).

Quote:

Out of interest what were the symptoms of the faulty modulator chip ?
It didn't work at all. The faulty chip (IC.5) was drawing lots of current. The 5V for the FPGA was down to about 1.5V. It was easy enough to diagnose, after I burnt my finger on it:).

David

1100 man 12th Feb 2019 11:37 pm

Re: Hedghog standards converter
 
Well done Dave!! :thumbsup: I think I'll order several modulator chips in view of your & Frank's experiences. At least they've got reasonable pin spacing so not the end of the world to remove one from the board.

I could only find one Ebay listing for them and that from China. Aliexpress also seems to have several. Where did you get yours?

How easy was it to program up the FPGA? I assume you used a Windows machine? I'm going to have to try with a PC running Linux as that's all I have access to but someone else said they couldn't get it to work using Linux.

Mind you, I've got to hone my SMD skills which as yet are non existent!

All the best
Nick


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