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 11 
 on: June 20, 2024, 09:32:02 AM 
Started by RolandSWL - Last post by WB6NVH
Yes indeed

 12 
 on: June 19, 2024, 12:27:35 AM 
Started by RolandSWL - Last post by KD6VXI
In the early 80's I was manager of the ham department in a large electronics store in San Jose, CA. Long gone now. We were a Rohn dealer and carried 25 and 45 series sections.  At that time a 10 foot section of 25G was $ 65 and we would loan you the gin pole.  I had any number of customers who would come in and complain that Texas Towers sold 25G sections for some $ 20 cheaper and there was no sales tax. I would try to explain that the shipping would kill all of that, but they would have none of it.  They were sure there was free shipping and would not be talked out of the idea.

California has pretty mild weather other than right on the ocean so towers last a long time.  You can usually get a free 50-75 foot one out here but the devil is in the details.  I have a friend in Long Beach who just had his 65 foot Rohn 45G taken down two days ago as he is moving out of state, and it is headed to the scrap yard.  He just doesn't want to deal with it.  The crazy situations are where there will be an ad on Craigslist where it says "Free tower, grandpa died and his house is sold and we need it out of here. You take down and haul away."  I cringe when I see this. The liability issues are massive.

The age of nice towers in residential areas is coming to an end in most of the country.  Neighbors, HOA's and city codes are all against it.  Not that it would affect you in the country, but the law of supply and demand means towers will get more expensive and harder to source.

Smart dealers won't sell caged crank-up towers. Too risky, some fool will try to climb one.  But those usually are 50 feet or less and don't fit your plans anyway. 

None of this really answers your questions but the topic jogged my memory.

Quement?

--Shane
WP2ASS / ex KD6VXI

 13 
 on: June 18, 2024, 03:11:34 PM 
Started by RolandSWL - Last post by RolandSWL
Not at all Geoff. It is food for thought. Free usually means the lower lumbar pays the check.

 14 
 on: June 18, 2024, 02:36:00 PM 
Started by W2TRH - Last post by W2TRH
Hello Gent's apoigies for not getting back to the list here, lot's going on at my QTH , the hammond solution looks great and jersey fest and near fest i will be on the look out for parts receivers too as we have other receivers on the Slater like it , when it it failed i had to say, I love the smell of burnt transformer in the afternoon Smiley thank you for your time and effort,
Steve
W2TRH

 15 
 on: June 18, 2024, 07:45:16 AM 
Started by ko4nrbs - Last post by KB1VWC
  I agree with Jim.  Figure out if the hum is 120Hz or 60Hz before you start messing with capacitors.  All DX60's in AM mode have some 60Hz induced in their audio because of the 12AX7's  filament wiring being unbalanced and using the chassis for the filament return.  Twisted pair wiring for the filaments improves this with the ground placed back where the filament winding actually grounds to the chassis.  Making up a DC supply will improve it more.  It never goes away easily.

    Remember these are not Hi-Fi tube audio amps where single point grounding techniques were employed to minimize 120Hz and 60Hz. Filaments don't float with a hum balance pot.  When it was designed, no one cared if the audio dropped precipitately below 200Hz anyway. No one cared if it had some hum.

Steve
KB1VWC 
 

 16 
 on: June 18, 2024, 03:32:40 AM 
Started by G4OJY - Last post by G4OJY
I'm restoring a Harvey Wells T90 transmitter, but someone has removed the panel meter. The manual only gives a HW part number, so does anyone know what the sensitivity of the HW meter is?

Thanks

Andy G4OJY

 17 
 on: June 17, 2024, 10:01:17 PM 
Started by RolandSWL - Last post by WB6NVH
In the early 80's I was manager of the ham department in a large electronics store in San Jose, CA. Long gone now. We were a Rohn dealer and carried 25 and 45 series sections.  At that time a 10 foot section of 25G was $ 65 and we would loan you the gin pole.  I had any number of customers who would come in and complain that Texas Towers sold 25G sections for some $ 20 cheaper and there was no sales tax. I would try to explain that the shipping would kill all of that, but they would have none of it.  They were sure there was free shipping and would not be talked out of the idea.

California has pretty mild weather other than right on the ocean so towers last a long time.  You can usually get a free 50-75 foot one out here but the devil is in the details.  I have a friend in Long Beach who just had his 65 foot Rohn 45G taken down two days ago as he is moving out of state, and it is headed to the scrap yard.  He just doesn't want to deal with it.  The crazy situations are where there will be an ad on Craigslist where it says "Free tower, grandpa died and his house is sold and we need it out of here. You take down and haul away."  I cringe when I see this. The liability issues are massive.

The age of nice towers in residential areas is coming to an end in most of the country.  Neighbors, HOA's and city codes are all against it.  Not that it would affect you in the country, but the law of supply and demand means towers will get more expensive and harder to source.

Smart dealers won't sell caged crank-up towers. Too risky, some fool will try to climb one.  But those usually are 50 feet or less and don't fit your plans anyway. 

None of this really answers your questions but the topic jogged my memory.

 18 
 on: June 17, 2024, 06:57:32 PM 
Started by Steve - K4HX - Last post by Steve - K4HX
.

 19 
 on: June 17, 2024, 01:59:28 PM 
Started by ko4nrbs - Last post by WD5JKO

I like to try and define the problem first before pondering solutions...
I would try to find an online SDR receiver that you can hit with a good signal. Is there any audible hum?
 If so, can you determine if it 60hz or 120hz? Does the hum go away in CW mode, key down? If the hum peaks as QSB drops the carrier level, you might have some FM.
Try a crystal instead of a VFO. Any difference?

Jim
wd5JKO

 20 
 on: June 16, 2024, 09:50:55 PM 
Started by ko4nrbs - Last post by n8fvj
Stated by other poster you exceed tube current ratings, but the DX-60 does not have a rectifier tube. Use the higher rated capacitors, the increased charging current is very small. Tubes are rated for maximum capacitance with capacitor input filter, follow the recommendation.

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