Modulators - who's got what ? - UK Vintage Radio Repair and Restoration Discussion Forum

BassoonBloke · 11th Apr 2006, 2:58 pm

Hello People,

Continuing on from a previous conversation, who's got what modulator and what do you think of it's performance.
I have a ETF modulator from America (via Steve McAvoy) and having only completed it a short while ago (considering i've had the board for over a year!!) i must admit that i think i'm getting really good results.
I'm using it on a Bush TV12AM and a Pye LV20.
Anyone have any views on who can supply the best 405 line tapes (films / documentries e,t,c)
I recently got a semi pro vhs player from fleabay for a fiver +P&P and it gives great results (a PANASONIC AG 5260).

Alan.

ppppenguin · 11th Apr 2006, 3:10 pm

May I suggest you buy a standards converter and then you can show any material on your TVs. I will be reviewing the new Aurora converter very shortly and if the original was anything to go by it will be good. The new Aurora has an integral modulator switchable to any of the 13 channels and costs $260 (about £150). If you are at all serious about vintage TV it's difficult to argue at that price.

http://www.auroravideosys.com/converter/

Dave Moll · 11th Apr 2006, 3:14 pm

The only modulator that I have in working order is the one integral to my Domino standards convertor.

I have an ETF modulator which I have gradually been building and is just about completed but as yet untested, which I intend to use for other 405-line sources such as my test card generator - currently running at 625 and feeding the Domino.

If I ever succeed in acquiring a pattern generator with built-in modulator, I will investigate the possibility of installing the ability to switch between the internal signal and an external one.

evingar · 11th Apr 2006, 3:22 pm

Hi Basson Bloke and welcome, good to see another 405 Line TV enthusiast

In answer to your question, I use a Dinosaur modulator, unfortunately no longer available.

With respect to 405-line video, mine is generated from a Pineapple based standards converter (built from odds and sods left over from the original project, with some some of my own mods).

If you want a small relatively cheap (no price published yet AFAIK) "no fuss" standards converter, Aurora will very soon be producing one - If feel like getting more involved, also see the active threads on the Darius analogue converter and Kat Manton's standard PC standards converter.

**Edit -

while I was faffing around posting and making a cup of tea, I notice Jeffrey has given a price for the Aurora - Agreed, looks like a "no-brainer" price wise, I'll be sorely tempted to get one another at that kind of dosh, especially with modulator built in

Sean Williams · 11th Apr 2006, 4:03 pm

I too have the ETF modulator, and have built the "Darius Modulator" as discussed on this forum.

I do find the Darius unit to give better results, and I look forward to the standards converter to follow soon!

Cheers
Sean

Kat Manton · 11th Apr 2006, 4:08 pm

Hi,

I've not got a working modulator as yet - and only one television set so far - a Sony 9-90UB dual--standard 9" portable - though now I can watch off-air TV and DVDs on them, 405-line sets (maybe 441 and 819-line sets too) may well proliferate.

I have the bits to build Steve McVoy's modulator; but haven't built it yet - I'm too busy now on what has rapidly evolved into a multistandard PC-based PVR project.

What I would like for myself is one single box with an HD-15 connector to connect to the PC graphics card, and an RF output, with channel and standard selection (which could be automatic.) I may well end up working on such a device; I've always wanted to learn more about digital frequency synthesis and this could be a good excuse

Regards, Kat

Panrock · 11th Apr 2006, 4:32 pm

I've still got my 'David Looser' modulator, going strong ever since 1983 and originally built before he published the design in Television magazine.

I also now have the modulator which came as part of the Domino converter, with its input now available for independent access. (yes, Malcolm did give me permission to do this

)

Steve

tvden · 11th Apr 2006, 5:11 pm

Hi all well I have a Domino, and a half built Etf modulator for Birmingham, I can see a few secondhand standards convertors coming onto the market if the Aurora is being sold for £150, I could be tempted at that sort of money as you get a lot of standards and I have often wanted to buy a few foreign sets but was put off by the fact I would have to get convertors for them, but of course we now have Kats offering as well as Darius, spoilt for choice !!!! regards Den

ppppenguin · 11th Apr 2006, 5:30 pm

Quote:

Originally Posted by tvden

Hi all well I have a Domino, and a half built Etf modulator for Birmingham, I can see a few secondhand standards convertors coming onto the market if the Aurora is being sold for £150, I could be tempted at that sort of money as you get a lot of standards and I have often wanted to buy a few foreign sets but was put off by the fact I would have to get convertors for them, but of course we now have Kats offering as well as Darius, spoilt for choice !!!! regards Den

The new Aurora is not multistandard. The output standard is pre-set during manufacture and while it is possible to reconfigure it with the correct equipment this is a long way from true switchability. There are also a few minor component value changes for the different standards.

tvden · 11th Apr 2006, 6:32 pm

Jeffrey I stand corrected

I was prob thinking of the original, still I suppose for the money its still a reasonable deal, much better than having to build one regards Den

evingar · 11th Apr 2006, 6:44 pm

Quote:

May I suggest you buy a standards converter and then you can show any material on your TVs. I will be reviewing the new Aurora converter very shortly and if the original was anything to go by it will be good. The new Aurora has an integral modulator switchable to any of the 13 channels and costs $260 (about £150). If you are at all serious about vintage TV it's difficult to argue at that price.

Just had a look at the Aurora web site - That thing is tiny!!!! It would be feasible to house inside most 405 Line TV cabinets - Maybe a little too expensive consider one for every TV in the collection though

ppppenguin · 11th Apr 2006, 6:49 pm

Quote:

Originally Posted by evingar

Just had a look at the Aurora web site - That thing is tiny!!!!

I know. I've been warned to glue it down when demo-ing it at the NVCF as it might grow little legs and walk off

oldeurope · 12th Apr 2006, 4:33 pm

Building a modulator yourself makes still sense.
For a transconductance modulator you need ony the oscillator
and the transconductance modulator transistor.
Two transistors. Look here for fundamentals :
http://bs.cyty.com/menschen/e-etzold.../uvb/uvb_e.htm

From the aurora output you need only a PNP emitter follower for
the biasing.
I read that the aurora gives no output in the bypass mode. So you need
an UVB for the biasing if you want to playback 405 vhs tapes etc.
I'll make loaded boards for the npn vision positiv modulator in summer and
will sell them with ready aglined London/Birmingham filters.

Kind regards
Darius

ppppenguin · 12th Apr 2006, 5:03 pm

Quote:

Originally Posted by Darius

I read that the aurora gives no output in the bypass mode. So you need an UVB for the biasing if you want to playback 405 vhs tapes etc.

I'm not sure what you mean. In bypass mode, if you put a valid video signal into the video input the output will be a correctly modulated signal. If you remove the video input the vision carrier will (I think) go zero level.

If you have a standards converter why would you want to use 405 line tapes anyway?

oldeurope · 12th Apr 2006, 6:00 pm

Quote:

Originally Posted by ppppenguin

I'm not sure what you mean. In bypass mode, if you put a valid video signal into the video input the output will be a correctly modulated signal. If you remove the video input the vision carrier will (I think) go zero level.

If you have a standards converter why would you want to use 405 line tapes anyway?

See page 6 Composite Video Output.

The same reasons why you make tapes on 625.
I have some 405 films I don't have in 625.
Of course you can playback vhs with the aurora modulator in bypass mode.
That is why it has this mode.

Kind regards
Darius

Dave Moll · 12th Apr 2006, 6:02 pm

Quote:

Originally Posted by ppppenguin

If you have a standards converter why would you want to use 405 line tapes anyway?

Surely, if you are going to record video to play back on 405 lines and you have a VHS recorder suitable for recording at 405, you will get a better 405-line picture if the recording is done after standards converting than before, due to the loss of resolution at 625 lines caused by the limited bandwidth of VHS recording.

oldeurope · 12th Apr 2006, 6:05 pm

Quote:

Originally Posted by tvden

Jeffrey I stand corrected

I was prob thinking of the original, still I suppose for the money its still a reasonable deal, much better than having to build one regards Den

Hi, building equipment and repairing is part of the hobby, isn't it

?

Kind regards
Darius

gdTV · 12th Apr 2006, 6:40 pm

Quote:

Originally Posted by Darius

Hi, building equipment and repairing is part of the hobby, isn't it

?

Hi Darius,

Absolutely right

If given an unlimited budget to buy at least one of all the commercially produced, and excellent I'm sure, standards convertors / modulators, I'd still 'need' to build one myself (which may not be so excellent but hopefully work reasonably). The other facet, for me personally, is to self-design it, even if some basic concepts are borrowed from elsewhere.

So, even with the temptation to buy a low cost Aurora at that price, the recent purchase on ebay of the correct video card and download of Gentoo Unix to set-up one of Kat's 405 line PVR's, and watching the analogue convertor schematics and kit developing nicely, I'm still persisting with bits of veroboard, various fifo's and eproms to build something unique.

To do this requires an interest in modern and vintage electronics however. This is where I think some of the distinction lies between folk who want to do it all for the technological challenge, and others who just want an easy signal source to enjoy their vintage electronics. Each to their own

Graham.

peter_scott · 13th Apr 2006, 4:34 pm

Quote:

Originally Posted by BassoonBloke

Hello People,

Continuing on from a previous conversation, who's got what modulator and what do you think of it's performance.

Alan.

I built Darius' original standards converter and Ch1 modulator. The modulator was very simple to construct and is delightfully stable in operation.

Peter.

DoctorWho · 15th Apr 2006, 6:10 pm

I use a very old modulator, built way back in the late 1980's and based on David Loosers excellent design. It's been going strong ever since and gives superb results. It has an extremely powerful output and can be received quite a distance away. he only downside is that it causes localised interference on UHF - but I can live with that. It is Channel 1 only.

My standards converter is a hand-made unit constructed for me by David Boynes (thanks again David), it's a superb unit and is in use every day. It is housed in a metal case and gives very good 405 pictures.

405 is on in our house daily.

Peter.

11th Apr 2006, 2:58 pm	#1
BassoonBloke Pentode Join Date: Feb 2006 Location: East London, UK. Posts: 231	Modulators - who's got what ? Hello People, Continuing on from a previous conversation, who's got what modulator and what do you think of it's performance. I have a ETF modulator from America (via Steve McAvoy) and having only completed it a short while ago (considering i've had the board for over a year!!) i must admit that i think i'm getting really good results. I'm using it on a Bush TV12AM and a Pye LV20. Anyone have any views on who can supply the best 405 line tapes (films / documentries e,t,c) I recently got a semi pro vhs player from fleabay for a fiver +P&P and it gives great results (a PANASONIC AG 5260). Alan.

11th Apr 2006, 3:10 pm	#2
ppppenguin Retired Dormant Member Join Date: Dec 2003 Location: North London, UK. Posts: 6,168	Re: Modulators - who's got what ? May I suggest you buy a standards converter and then you can show any material on your TVs. I will be reviewing the new Aurora converter very shortly and if the original was anything to go by it will be good. The new Aurora has an integral modulator switchable to any of the 13 channels and costs $260 (about £150). If you are at all serious about vintage TV it's difficult to argue at that price. http://www.auroravideosys.com/converter/

11th Apr 2006, 3:14 pm	#3
Dave Moll Dekatron Join Date: Feb 2005 Location: West Cumbria (CA13), UK Posts: 6,127	Re: Modulators - who's got what ? The only modulator that I have in working order is the one integral to my Domino standards convertor. I have an ETF modulator which I have gradually been building and is just about completed but as yet untested, which I intend to use for other 405-line sources such as my test card generator - currently running at 625 and feeding the Domino. If I ever succeed in acquiring a pattern generator with built-in modulator, I will investigate the possibility of installing the ability to switch between the internal signal and an external one.

11th Apr 2006, 3:22 pm	#4
evingar Octode Join Date: Oct 2003 Location: Newbury, Berkshire, UK. Posts: 1,770	Re: Modulators - who's got what ? Hi Basson Bloke and welcome, good to see another 405 Line TV enthusiast In answer to your question, I use a Dinosaur modulator, unfortunately no longer available. With respect to 405-line video, mine is generated from a Pineapple based standards converter (built from odds and sods left over from the original project, with some some of my own mods). If you want a small relatively cheap (no price published yet AFAIK) "no fuss" standards converter, Aurora will very soon be producing one - If feel like getting more involved, also see the active threads on the Darius analogue converter and Kat Manton's standard PC standards converter. *Edit - while I was faffing around posting and making a cup of tea, I notice Jeffrey has given a price for the Aurora - Agreed, looks like a "no-brainer" price wise, I'll be sorely tempted to get one another at that kind of dosh, especially with modulator built in __________________ Chris Last edited by evingar; 11th Apr 2006 at 3:28 pm.*

11th Apr 2006, 4:03 pm	#5
Sean Williams Dekatron Join Date: Feb 2005 Location: St.Ippolyts, Hitchin, Hertfordshire QRA IO91UW Posts: 3,517	Re: Modulators - who's got what ? I too have the ETF modulator, and have built the "Darius Modulator" as discussed on this forum. I do find the Darius unit to give better results, and I look forward to the standards converter to follow soon! Cheers Sean __________________ Engineers make things work and have spare bits when finished

11th Apr 2006, 4:08 pm	#6
Kat Manton Retired Dormant Member Join Date: Jul 2005 Location: West Yorkshire, UK. Posts: 1,700	Re: Modulators - who's got what ? Hi, I've not got a working modulator as yet - and only one television set so far - a Sony 9-90UB dual--standard 9" portable - though now I can watch off-air TV and DVDs on them, 405-line sets (maybe 441 and 819-line sets too) may well proliferate. I have the bits to build Steve McVoy's modulator; but haven't built it yet - I'm too busy now on what has rapidly evolved into a multistandard PC-based PVR project. What I would like for myself is one single box with an HD-15 connector to connect to the PC graphics card, and an RF output, with channel and standard selection (which could be automatic.) I may well end up working on such a device; I've always wanted to learn more about digital frequency synthesis and this could be a good excuse Regards, Kat

11th Apr 2006, 4:32 pm	#7
Panrock Nonode Join Date: Feb 2005 Location: Worcestershire, UK. Posts: 2,533	Re: Modulators - who's got what ? I've still got my 'David Looser' modulator, going strong ever since 1983 and originally built before he published the design in Television magazine. I also now have the modulator which came as part of the Domino converter, with its input now available for independent access. (yes, Malcolm did give me permission to do this ) Steve

11th Apr 2006, 5:11 pm	#8
tvden Retired Dormant Member Join Date: Oct 2003 Location: Halesworth, Suffolk, UK. Posts: 413	Re: Modulators - who's got what ? Hi all well I have a Domino, and a half built Etf modulator for Birmingham, I can see a few secondhand standards convertors coming onto the market if the Aurora is being sold for £150, I could be tempted at that sort of money as you get a lot of standards and I have often wanted to buy a few foreign sets but was put off by the fact I would have to get convertors for them, but of course we now have Kats offering as well as Darius, spoilt for choice !!!! regards Den

11th Apr 2006, 6:32 pm	#10
tvden Retired Dormant Member Join Date: Oct 2003 Location: Halesworth, Suffolk, UK. Posts: 413	Re: Modulators - who's got what ? Jeffrey I stand corrected I was prob thinking of the original, still I suppose for the money its still a reasonable deal, much better than having to build one regards Den

12th Apr 2006, 4:33 pm	#13
oldeurope Retired Dormant Member Join Date: Dec 2003 Location: Solingen, Germany Posts: 727	Re: Modulators - who's got what ? Building a modulator yourself makes still sense. For a transconductance modulator you need ony the oscillator and the transconductance modulator transistor. Two transistors. Look here for fundamentals : http://bs.cyty.com/menschen/e-etzold.../uvb/uvb_e.htm From the aurora output you need only a PNP emitter follower for the biasing. I read that the aurora gives no output in the bypass mode. So you need an UVB for the biasing if you want to playback 405 vhs tapes etc. I'll make loaded boards for the npn vision positiv modulator in summer and will sell them with ready aglined London/Birmingham filters. Kind regards Darius

15th Apr 2006, 6:10 pm	#20
DoctorWho Rest in Peace Join Date: Apr 2005 Location: Devon Posts: 850	Re: Modulators - who's got what ? I use a very old modulator, built way back in the late 1980's and based on David Loosers excellent design. It's been going strong ever since and gives superb results. It has an extremely powerful output and can be received quite a distance away. he only downside is that it causes localised interference on UHF - but I can live with that. It is Channel 1 only. My standards converter is a hand-made unit constructed for me by David Boynes (thanks again David), it's a superb unit and is in use every day. It is housed in a metal case and gives very good 405 pictures. 405 is on in our house daily. Peter.