Finally finished cracking the passwords on the #analogcable headend. All I'm going to say is, the default password is pretty bad if you're in the TV industry, I'm stunned that on this live system it was never changed, and I'm no longer surprised that someone wrote a Phrack article on finding these systems and getting in...

I guess this evening I'll be updating the #analogcable headend to OS version 4.1 or 4.1.1, then the AHA-2940 should work.

IT LIVES! #analogcable

Project #analogcable continues... The HBA and VGA card are in, motherboard IDE disabled, now I'm booted into the maintenance kernel...

I do at least have the #analogcable headend software running under emulation - albeit slightly borked because of a bug in 86box.

Found a UK model GI Intercon 7000 cable box on ebay. Security seals intact. Not been messed with from what I can tell. And that looks like the Mitsubishi MELPS740 variant from the MVP scrambler. Hmm. I wonder if they went with an external ROM. #analogcable

So close and yet so far... #analogcable

Some progress with #analogCable - an iDP711x/210 UK cable box turned up on ebay the other day - which I've snapped up. I'm hoping it has the older customised Mitsubishi MELPS740 CPU which doesn't encrypt the data bus -- and which I've already mostly figured out from the MVP scrambler reverse-engineering.
In theory if I can get a good code dump from an older box, I should be able to disassemble it and figure out the commands for frequency mapping, PPV event info and callback...

When I get that #analogCable headend built, I'm going to have a channel that's 24/7 Defcon talks, and another that's 24/7 Computer Chronicles.
Anyone have other suggestions for TV channels I should have?

I'm looking for a copy of the Jerrold / GI / Motorola "Addressable Control Computer" (ACC, aka ACC-4000, 3000 or 2000) software, or Jerrold Terminal Configurator software, if anyone has it. Would have been used in 1980s/90s Cable TV headends and repair centres.

Install media, backups, old HDD, anything is good.

I'm also interested in service software e.g. Terminal Configurator - or any other Jerrold/GI software.

I'd like to get my CATV headend working!
Boosts appreciated.
#AnalogCable

Hi there, I'm Phil

I'm currently giving mastodon.radio a try, thanks to the admins for having me!

I'm a #maker, with #electronics and (some) #metalworking skills. I'm also a #hamradio #AmateurRadio operator with a UK full licence, under callsign M0OFX (and one of the three joint and equal holders of the M0YIP club).

I'm also into #ReverseEngineering and currently working on the Jerrold/GI Analog Cable TV system (see #analogcable) and hoping to build my own #CATV head-end.

#introduction

Wow, I just found a list price for the Jerrold MVP Modulating Video Processor (cable TV video scrambler). $2600, in 1988.
If you account for inflation, that's $6684.11 in today's money. #analogcable
https://archive.org/details/sim_satellite-communications_1988-09_12_9/page/n63/mode/2up?q=%22modulating+video+processor%22

#AnalogCable box repair part one - this CFT2100 board now has a battery holder. The original battery was stone dead.
Next up - RAM CS, OE, WR taps and a switch for the modchip.

The more I prat around implementing my #analogcable headend, the more I think that a forms-based UI like TN3270 would be great for it. SSH in and control everything from there.
Shame I can't find a 3270 data stream/server or general text-mode UI library I like...

Jerrold cable headend gear has an Aesthetic. Also I have a new toy, a Jerrold C6M modulator. Anyone got a manual? #analogcable

I had a ponder on my lunch break - what is the Plessey MJ2841 64x4 FIFO in the #JerroldMVP scrambler for? It's wired to the Timing Controller FPGA.

The theory of operation gives a tantalising clue: "scene detection is done by correlation".

This patent fills in the gaps: https://patents.google.com/patent/US4353088A
It's by Oak Communications but was later reassigned to General Instrument. Interestingly it's by Ir. Pieter den Toonder, the founder of Irdeto.
#analogcable

Tonight in #analogcable, feeding the IF-out from the scrambler (in RF mode) into a HackRF One. Turns out --
- the output spectrum is inverted
- the video IF carrier is around 45.745 MHz
- the audio IF carrier is around 41.25 MHz
This is useful to know... although I have the matching Jerrold modulator on the way (the Commander C6M)

There's probably a really easy way to make copies of these security pins... Model each side in Inkscape, export to DXF, import into OpenSCAD, extrude, cut out the notch, 3D print. Hmm. #analogcable

Another #analogcable box just arrived. This is a GI/Jerrold DPV7212, an IMPULSE 7000 OneWay unit, with volume control, expansion ROM, and fixed channel 2 output. This looks like a fairly early unit.

More #analogcable fun - this evening I've been reverse-engineering the Jerrold RF scrambling scheme.

The scrambler hides scrambling data by amplitude-modulating the audio subcarrier.

First photo shows a scope probe tapping the Audio IF attenuator enable pin. The second shows the data and timing pulses on that pin alongside the video signal.

All documented here:
https://www.philpem.me.uk/hacktv/analogcable/gi_scrambling

Next I need to rope @fsphil into some discussions about the best way to add all this to HackTV...