Clearly sounds like an instance of RF getting the IR sensor circuit for
the TV. I experienced that problem with my Direct TV receiver as it
turned on and off and changed channels with SSB transmissions. They had
to replace the Direct TV receiver to correct the problem.
I don't agree with the central ground point utilization unless it is the
station power supply which is the only DC zero voltage point. That DC
voltage point should be connected to the external ground {if used} and
should be connected direct to each piece of equipment, transceiver, amp,
tuner and etc. Although Jim and I don't agree, I don't daisy-chain
equipment grounds. And I don't suggest using an external ground as I've
found those to be more problematic than problem solving. Remember the
ground lead acts as an antenna and will pick up RF which means one end is
ground and the other end is above ground in terms of RF depending on
length and frequency.
On the Centurion, no harm at operating at max rated plate current {abt
0.8A} and max rated grid current {abt 240ma}. If you're not attaining
these, this says the amp may not be loaded correctly for the drive
applied. My Centurion produces 1200 watts out on the Bird 43P with 80
watts of drive on 20M. The 1200W is amp power as measured less drive
power. In actuality, the Bird shows nearly 1350 watts out at "full tilt
boogie" with 100 watts of drive. Remember in a GG amp the drive power is
part of the total output power.
73
Bob, K4TAX
> One TV in question is stand alone..no external speakers. Tuning the
> station
> will cause that TV to switch on and then you can't turn it off without
> unplugging it and letting it sit for a while. My modulation or keying
> also
> comes from the speakers. Didn't have any of that with the other station.
> Nothing else has changed. I've added nothing, removed nothing in any of
> the
> audio/TV systems.
>
> I'll try some common mode filter chokes on the power cables. Just
> thought
> it strange that with the old station the only problems I had was the nice
> touch sensors I put in my wifes china and curio cabinets for the lights.
> Shouldn't have done that. Nothing stops those from blinking...nature of
> the
> beast.
>
> The station is all tied to a central point ground panel in the shack that
> is
> tied via 2/0 copper to the ground system that consists of a ring at the
> base
> of the tower and several near 100' radials leading away from the shack
> off
> the ring with 10' ground rods driven 20'. All done with 2/0 copper 7
> strand
> cable and exothermic welded to all rods and at three points at the base
> of
> the tower. All of that is tied to the shack and house electrical panels
> to
> meet code for safety grounds and keep everything at the same ground
> potential point. The tower is 100' from the shack and 200' from the
> house.
> All coax runs are burried in a 4" conduit and protected by ICE protection
> blocks at the central point ground as well as all rotor cables which are
> protected with ICE blocks at the tower base and the central point ground
> at
> the shack.
>
> I do this stuff for a living on sites that have to be on the air in the
> middle of storms.
>
> I realize none of that has much to do with whether I'm turning on the
> TV's
> in the house or entering the audio systems but just to eliminate any
> concerns about a decent RF ground system.
>
> Thanks for you guys suggestions and send any further that you might have.
> I'd like to minimize this as much as possible.
>
> Oh and by the way the Centurion has had a Peter Dahl overwound
> transformer
> installed so around 65 watts generates around 1400 watts on my Bird
> meter....I tune it for max output at 50 watts drive and get around
> 1100watts
> out and then retune the load to reduce the grid current to a point just
> before the output starts to drop off. I wouldn't think running the amp
> at
> max rated grid current to be a good thing...but suggestions are welcome.
>
> Cecil
>
> ----- Original Message -----
> From: "Robert Mcgraw" <rmcgraw@blomand.net>
> To: "Discussion of Ten-Tec Equipment" <tentec@contesting.com>
> Sent: Monday, May 14, 2012 11:25 AM
> Subject: Re: [TenTec] Transmitter specs (was Top receivers)
>
>
>> Experience and practice dictates that if audio equipment picks up RF it
>> is not the fault of the RF generating equipment. It is more likely RF
>> being picked up on speaker lines and other cables, power and such that
>> is
>> being detected in the audio stages, be the system on or off. Common
>> mode
>> chokes on speaker lines, power lines and other audio cables is likely
>> the
>> true cure.
>>
>> Why did the other station not cause the problem? Can't say. I do hope
>> that you have each piece of the new station connected back to the power
>> supply ground terminal. That then is the common point ground for the
>> station.
>>
>> I run my Omni VII or the Eagle into the Centurion amp developing full
>> rated output. My TV and surround system is immediately below the ham
>> station, the tower is 3 ft outside of the wall behind the TV and sound
>> system and the off-air TV antenna is side mounted on the ham tower. No
>> RFI at my house, any band, any mode. Also I do not use any external
>> station ground as the station is on the 2nd floor of a wood frame
>> house.
>> All lightning protection is outside of the house and mounted on the
>> radio
>> tower at the point the coax, balanced feed lines and rotor cables enter
>> the house.
>>
>> On tuning an amp. Always tune for maximum output. Do so by advancing
>> drive until you attain rated PA grid current max and rated PA plate
>> current. Adjust TUNE for maximum output and LOAD for rated grid
>> current,
>> thus more loading = less grid current. With the Centurion the marks on
>> on the PA plate and PA Grid meters are very clear as to the maximum
>> value
>> allowed. The Centurion will attain rated output with anywhere between
>> 80
>> watts to 100 watts of drive. It will vary band to band.
>>
>> If you wish to operate at a lower power then simply reduce drive. NEVER
>> retune the amp for lower power.
>>
>> 73
>> Bob, K4TAX
>>
>>
>>> Sorry changed the subject line since the subject has changed...
>>>
>>> This comes at a time when I am trying to make sense of some problems
>>> with
>>> my
>>> station. I'm a recent Ten-Tec convert having bought a used Orion II
>>> and
>>> Centurion amp. Was using a Yaesu FT-1000MP MKV and a modified
>>> Clipperton
>>> L
>>> prior. Since putting the Ten-Tec gear online my wife is complaining
>>> that
>>> I
>>> am coming through many different things in the house (shack is in a
>>> separate
>>> building) that I never had problems with before. TV audio in two
>>> rooms
>>> mainly. I get complaints from her even if I am only running the rig
>>> at
>>> 100W
>>> so I don't believe the amp is a contributor other than making the
>>> problem
>>> stronger.
>>>
>>> When using the amp I drive it with 50 watts out of the rig and tune to
>>> 1KW
>>> peak out using CW dits as recommended by Ten-Tec. Amps not pushed
>>> hard
>>> and
>>> neither is the rig.
>>>
>>> My grounding system is very robust...near commercial/cellular spec for
>>> lightning protection and all equipment is bonded to it. Really
>>> nothing
>>> has
>>> changed in my station except the transceiver and amp. Antennas are
>>> resonant
>>> on 10 thru 20 and 40. (Force 12)
>>>
>>> I plan to put my spectrum analyzer on the air next chance I get and
>>> see
>>> just
>>> what is going out. I didn't expect this and am concerned about what
>>> the
>>> neighbors might be experiencing but haven't come knocking on my door
>>> as
>>> of
>>> yet.
>>>
>>> Old rig was a 200W version of the MKV run at about 125 watts into the
>>> amp
>>> that was tuned up tight to about 900W out. I was pushing it much
>>> harder.
>>> I
>>> never ran the rig in Class A due to the heat and stress it created on
>>> the
>>> finals.
>>>
>>> Any thoughts and suggestions would be appreciated.
>>>
>>> I've had no on air complaints.
>>>
>>> Thanks
>>>
>>> Cecil
>>> K5DL
>>>
>>> ----- Original Message -----
>>> From: <d.e.warnick@comcast.net>
>>> To: "Discussion of Ten-Tec Equipment" <tentec@contesting.com>
>>> Sent: Monday, May 14, 2012 7:36 AM
>>> Subject: Re: [TenTec] Top receivers
>>>
>>>
>>>>
>>>>
>>>> There are currently emission standards, etc. that need to be met to
>>>> gain
>>>> FCC type acceptance. If the current crop of transceivers meet these
>>>> specifications & there is still a problem, then the specifications
>>>> for
>>>> FCC
>>>> type acceptanced may (or may not) need to be reviewed. There is a
>>>> specification for 'spurious emissions', as well as others. If they
>>>> are
>>>> not
>>>> doing the job, then a thoroug h review of those specs may be in
>>>> order.
>>>>
>>>> What we do not need is any government authority dictating engineering
>>>> such
>>>> as a specific type of component ("48v MOSFETs").
>>>>
>>>> Please, please, please allow the consumer to drive the market, and be
>>>> very
>>>> cautious about yet more government oversight where it has been proven
>>>> time
>>>> and again to increase cost without solving anything.
>>>>
>>>> Just my take.
>>>>
>>>>
>>>>
>>>> We could solve a lot of issues on the air by better educating those
>>>> among
>>>> us who overdrive, tune improperly, overprocess, and run fa r more
>>>> power
>>>> than necess ary. (Yes, I do use a linear when necessary.) In the
>>>> current
>>>> Yemen & Somalia DXpeditions, I have had far more issues with bad
>>>> operators
>>>> than with bad signals. (If I hear UP, LID, or worse one more time, I
>>>> think
>>>> I'll scream). I have shut down & walked away several times, even
>>>> though
>>>> I
>>>> need the band. My choice, but that's not the ham radio that I have
>>>> enjoyed
>>>> for more than 45 years, and I choose to not let it become that. There
>>>> are
>>>> guys calling without a break even though a contact is in progress. If
>>>> you
>>>> want more government intervention, fund the FCC's enforcement branch
>>>> to
>>>> clean this up. (No, I don't really want that either but something has
>>>> got
>>>> to give).
>>>
>>> _______________________________________________
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>>> TenTec@contesting.com
>>> http://lists.contesting.com/mailman/listinfo/tentec
>>>
>>
>>
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