NO FCC rf link?

Correct but usually those also spew out a whole picket fence of nasties at lower frequencies.

Yup, went the way of the buggy whip.

The main culprit was usually the deflection coil set and even more so the wires going to it. The spectrum analyzer really lit up when apporaching those with E-field and H-field probes.

Yes. The switch to digital was IME the beginning of TV's death spiral. Over-the-air reception has become unreliable, umpteen sub-channels were added and filled with mostly cheap programming. To the point where other than the evening news people like my wife and I no longer watch TV.

What should give station manager real concern is the youngest generation. I have met kids who don't really know what TV is anymore. "Do I watch that though an app?".

I just got a new license here in the US but had one in Germany for a long time. After a 35-year hiatus I went back on the air and was disappointed how much worse the noise has become. So much that, when in need of a new transceiver, I made sure it has very good and most of all hand-configurable noise reduction and blanking features. Next up will be an active receive loop that doesn't need to be constantly re-tuned.

For some hams the noise situation is so bad that they use a distant webSDR via Internet for receiving and turn their transceiver's audio volume to zero.

I thought thet the deflection coils and associated components belong to the line output stage.

That's what I assume Gray Wolf meant with "sweep output stage", as in horizontal or line. Since this was also the stage that acted as a large flyback power supply to generate the high voltage for the CRT those were a serious source of RFI.

In the more "modern" CRT color TV set they went a step farther and used the flyback stage to also drive the power supply for the whole set. Almost everything depended on everything else and that could drive even seasoned TV repairmen up the walls. However, that was shortly before the sad trend began where TV sets would no longer be repaired but instead chucked and replaced.

However, it was probably transmitting at 50kW. Crystal or piezo headphones are quite sensitive.

Nowadays you'd probably here buzzing, crackling, popping and warbling from all the modern day electronic detritus.

That was the IPSALO (Integrated Power Supply And Line Output) patented first by the Finnish manufacturer Salora Oy (later part of Nokia).

"B+ Boost" was a sort of flyback supply that made its own input voltage.

AFAIR it was almost all manufacturers that did this. If it only saved 10 cents they'd do it, to hell with serviceability. Plus they often made the HV transformer hard to remove and so expensive as a spare part that a repair was no longer economical.

That was after the original patent ran out.

Then Salora must have invented it in the 60's when the HV transformer was still driven by a tube :-)

If I read the patent correctly, he cleverly uses the deflection coil to provide zero current switching?

Patent excerpt:

According to the present invention there is pro vided a television receiver's line deflection output stage circuit arrangement for developing in a deflection yoke, a sawtooth wave current, compris ing scanning and return portions, comprising an input transformer with primary and secondary wind ings, a primary switch for connecting the primary winding of the input transformer to a power supply and a bidirectional secondary switch to connect the deflection yoke during the scanning stroke to a scan ning capacitor having the scanning voltage and to connect the energy storage condenser to the secon dary coil of the transformer, the mutual polarities of the primary and secondary windings of the transformer being suchthatfollowingturn-offofthe sec ondaryswitch the return pulse appearing on the secondary winding induces through the transformer in the primary winding a current which nullifies the current in the primary winding and so nullifies the current in the primary switch.

Further difference to the known circuits is created so that the operation of the scanning switch reacts upon the operation of a primary switch, so that the collector current of the primary switch becomes negative, as will be described later in more detail. As a result there will be no turn-off losses because there is no current and voltage at collector simultaneously.

so these RFM69 modules that seem to be popular (just ran across them) could be used in a product and not need FCC approval?

Klaus, that may be a (or the?) distinguishing feature here. Although I've come across several TV sets back in the 80's that used SCRs which also had to work in a similar fashion. The result was almost always the same, the HV transformer was bad and the manufacturer either would not sell any to the general public or they were prohibitively expensive. IOW you diagnosed a set and then the owner wanted to abandon the repair because of that cost. I just hung it all up at that point.

If you want to use it in a product I would always ask the manufacturer and get the certification copies in writing. I think in this case that would be Hope RF. It is a Chinese company, in Shenzhen.