• Get involved.
    We want your input!
    Apply for Membership and join the conversations about everything related to broadcasting.

    After we receive your registration, a moderator will review it. After your registration is approved, you will be permitted to post.
    If you use a disposable or false email address, your registration will be rejected.

    After your membership is approved, please take a minute to tell us a little bit about yourself.
    https://www.radiodiscussions.com/forums/introduce-yourself.1088/

    Thanks in advance and have fun!
    RadioDiscussions Administrators

HD Power Increase

nd2023

Banned
Are many stations even going to bother increasing their HD power? For many full power stations, increasing the HD power means buying a new transmitter, or significantly higher electric bills due to inefficiency. HD has not shown any return on investment so far, so would stations want to throw more money away?
 
Most HD transmitters were built with the assumption that eventually HD power levels would be increased, or analog broadcasts even curtailed. For most transmitters, its simply a matter of replacing a logic card or recalibrating a potentiometer...pretty easy stuff for an engineer to do.

Later . . . .
 
Matt Smith said:
Most HD transmitters were built with the assumption that eventually HD power levels would be increased, or analog broadcasts even curtailed. For most transmitters, its simply a matter of replacing a logic card or recalibrating a potentiometer...pretty easy stuff for an engineer to do.

Later . . . .

I respectfully disagree.
 
Nick said:
Are many stations even going to bother increasing their HD power? For many full power stations, increasing the HD power means buying a new transmitter, or significantly higher electric bills due to inefficiency. HD has not shown any return on investment so far, so would stations want to throw more money away?
Not to mention a bigger HVAC system...While I've never had the displeasure of seeing one of these albatrosses in action, they say the FM version borders on being an acceptable substitute for a furnace.
 
Matt Smith said:
Most HD transmitters were built with the assumption that eventually HD power levels would be increased, or analog broadcasts even curtailed. For most transmitters, its simply a matter of replacing a logic card or recalibrating a potentiometer...pretty easy stuff for an engineer to do.

Later . . . .

I'm in TV, not radio, but...

My understanding is that many stations implemented HD not by replacing an analog transmitter with a dual-mode unit, but by adding a digital transmitter to an existing analog rig.

In this case, we're talking about quadrupling the output power of the digital transmitter -- something that would go way beyond simple adjustments.

This "split" transmission method is amazingly inefficient. (the combiner that mixes the analog and digital power wastes the vast majority of the digital power as heat) At a 100kw station, this would mean going from wasting 9kw as heat to wasting 36kw. Not only is that a lot of electricity, but you have to spend more on ventilation/air conditioning to get that heat out of the building. I'm sure in practice, "hybrid" stations implementing the power increase will completely replace their transmitters - both the old analog unit and the digital "add-on" - with a new analog/digital dual-mode unit.

But again, that's not a simple adjustment.
 
36 kw of heat could be very useful. You could sell the heat to businesses up and down the block for extra income.
You could open a waterpark and have NO costs for heating the water or pool area.


In the summertime, you could afford to cool the whole mess with money you made over the winter.
 
Lol! "a simple potientiometer adjustment"..... Now that's some pretty funny s#*t! Only in Clear Channel and CBS' very lucid dreams of grandure!!!

The truth is that it's waaaaayyyyy to impractical for cash-strapped McCoporates right now to impliment at most of their chain stations. The technology that will improve the situation someday will be combining filters that will allow combining with much less loss by allowing main analog through the midddle from the analog transmitter and put the digital crap out on the edges via a seperate digital transmitter via another input into the system. All of this would be done with sharp filters instead of just hybrid combining and dumping the losses. Filters are currently pretty expensive and the size of them can be too big for the room. If enough stations go that route though the prices will come down. To make any -10 work IMHO will require everything going up the same coax. Any try at spacial combining INCLUDING eri's way of going in the reject port will create self-jamming of the analog host to the point most stations won't be happy with it. Filter combining is the onl real answer.
 
OKCRadioGuy said:
Lol! "a simple potientiometer adjustment"..... Now that's some pretty funny s#*t! Only in Clear Channel and CBS' very lucid dreams of grandure!!!

The truth is that it's waaaaayyyyy to impractical for cash-strapped McCoporates right now to impliment at most of their chain stations. The technology that will improve the situation someday will be combining filters that will allow combining with much less loss by allowing main analog through the midddle from the analog transmitter and put the digital crap out on the edges via a seperate digital transmitter via another input into the system. All of this would be done with sharp filters instead of just hybrid combining and dumping the losses. Filters are currently pretty expensive and the size of them can be too big for the room. If enough stations go that route though the prices will come down. To make any -10 work IMHO will require everything going up the same coax. Any try at spacial combining INCLUDING eri's way of going in the reject port will create self-jamming of the analog host to the point most stations won't be happy with it. Filter combining is the onl real answer.
There is one other answer...admit that it's a failure & shut 'em all down.
 
Except for some operators, especially public radio stations needing to carry more programming than can fit on one channel, it hasn't failed.
 
Matt Smith said:
Most HD transmitters were built with the assumption that eventually HD power levels would be increased, or analog broadcasts even curtailed. For most transmitters, its simply a matter of replacing a logic card or recalibrating a potentiometer...pretty easy stuff for an engineer to do.

Later . . . .

matt, stick to TV dude. Most of the HD installations I have come across were built for the rules at the time, there's very little, if any, headroom in the system. For one particular outfit I contract for, they would need to replace not only the transmitters, but the feedline, parts of the combining system and all the reject loads. They would have to rebuild there entire HD transmitting plant for very little return. They are public stations and it was a struggle for them to get HD on the air to begin with. With penetration of receivers at abysmal levels, chances are they will not be increasing power. The proposal was admission of a mistake in the first place, which is what this whole HD thing was to begin with.
 
HD is of great value to noncomms and public radio. You can't undo it. Work with it. Try to get the radios out there, and notice that more and more automakers are making HD a part of their offerings.
 
Status
This thread has been closed due to inactivity. You can create a new thread to discuss this topic.


Back
Top Bottom