First Vintage TV now under way – Hedgehog build questions!
 

Hi!

I have only two vintage TV projects planned, one was a valved TV with an isolated chassis and parallel heaters and the second is a Tyne–style CTV.

I will be collecting a PTV next Monday, so me thinks it's time to begin my Hedgehog Standards Converter – I've got the PCB and modulator chip laid in already, so my next purchase will be cheap "lab–kits" of resistors and capacitors – photos will be added to this new thread as construction proceeds!

I have downloaded Frank's latest software – I ordered the PCBs a few months ago – do I need to reorder a new PCB?

Can anyone advise me if only one PCB layout was released or was there more than one?

So far, I've heard of Hedgehog I, Hedgehog II and Hedgehog PSC!

Chris Williams

Re: First Vintage TV now under way – Hedgehog build questions!
 

Hi Chris,
The Hedghog I and II PCB's are very different and as far as I'm aware there was only one version of each made. You probably have the Hedghog II PCB. The PSC is different again with the display added and programmable.
If you look at Frank's web site you may be able to identify the board version you have.
One of the problems as of late is the availability of many components used in all the converters.
Mark.

Re: First Vintage TV now under way – Hedgehog build questions!
 

Hi!

Afternoon Mark!

I've checked Frank's site and you can't confuse the three designs!

I've just checked my JLC order history, which shows the Gerber Files as being for the Original MK1 Design with the plug–in FPGA board – I've already got the FPGA Board kit and two of the Modulator ICs, that leaves the TVP5150, switches, voltage regulator i.c.s, transistors, Rs, C's, Ls and the case to buy now, which I'll order next month!

Chris Williams

Re: First Vintage TV now under way – Hedgehog build questions!
 

The PYE PTV is a well built receiver. It has many wax caps on the swing out boards. The M3 'aluminium pea' style diodes will all need replacement. It has a massive reserve of gain and flywheel sync.
The CRT is either a AW36-20 [aluminised] or AW36-21 [non aluminised] both with electrostatic focus. The original blue Pye service manuals appear to be thin on the ground.
Good luck with it, they give an excellent picture. John.

Re: First Vintage TV now under way – Hedgehog build questions!
 

Hi Chris
Your question has already been answered but just to confirm.

Hedghog, Hedghog II and Hedghog PSC are different projects. Each has their own PCB. None of the PCB's has ever changed and it is very unlikely that any of them ever will.

Their firmware has changed. The latest firmware for each of them is on the web site.

It is important to use 0.1% type resistors for the R2R ladder. These are marked as 0.1% in the component list

Frank