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New tube type am transmitter

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New tube type am transmitter

So I purchased an am tube transmitter on eBay from a gentleman in Virginia who builds them. I paid a fairly high price, but I feel it's worth it. His design involved three tubes. It plugs into the wall, has a long wire coming out of the metal box, a nice audio cable as well. Had a post with nut  and washer for grounding. It can be tuned by a nice big knob from about 750 am up to 1100 am. It has a nice glow  from the tubes. Excellent audio for am. I'm playing old southern gospel music through it to my antique emerson radio. 

The range covers my small apartment building of about 16 apartment units. I haven't put a ground rod in the ground to see if that will extend my range somewhat yet, but I'm happy with housecasting really. 

There's not much worth listening to on am around here anyway. Talk, talk, and more talk. A couple classic country stations that play same songs everyday.BBN christian station to the north and that's about it. 

I really appreciate the fine American craftsmanship in this transmitter. I'll try to get some pics uploaded later.

I don't have sound boards and other contraptions, i just hook the audio cables to the pc and push the sound until it starts to distort, but honestly it's just as loud as the local talk am without distortion. Much better sound with music than my talking house, but the talking house range seems better. I use radio dj.

I plan on streaming old time radio shows thru it for the elderly neighbors.

Thought I would share.

Just an fyi he used are 12au6

Just an fyi the tubes used are 12au6, 12cs6 and 50hk6. I'm not familiar with different types of tubes, any input from anyone?

Old time radio

94.1 fm and 1090 AM KWWQ

Serving a tiny portion of leadington

And I should mention, no

And I should mention, no annoying hum.

Old time radio

94.1 fm and 1090 AM KWWQ

Serving a tiny portion of leadington

Picture?

Can you post a picture so we can see it?

 

 

Mark

I can't seem to get a pic

I can't seem to get a pic uploaded but here is a link to his transmitter on eBay. Pictures there.

 

http://m.ebay.com/itm/AM-BROADCASTER-TRANSMITTER-HEAR-YOUR-MUSIC-ON-ANTI...

Old time radio

94.1 fm and 1090 AM KWWQ

Serving a tiny portion of leadington

Like that

Nice, all hand done with no printed circuit boards....like things used to be.

 

Mark

My thoughts exactly. No

My thoughts exactly. No Chinese quality here. I'm thoroughly enjoying this transmitter. It drifted slightly while it was warming up, but has consistently stayed in 1100 am for the last 8 hours with no drift. Walking around it or touching the transmit wife has no effect on it like my talking house. Sipping tea, smoking my pipe, listening to sherlock Holmes on my emerson tube radio. Today has been a good day.

Old time radio

94.1 fm and 1090 AM KWWQ

Serving a tiny portion of leadington

To me that sounds like a good

To me that sounds like a good price, considering what you get. I mean it appears to be of excellent construction (not that I would actually know, but just looking it over gives me that impression). It doesn't look like just something thrown together, and in the guys description you get the sense of quality. The tubes is something that always attract me.

This link you provided showed limitted info, here's the same item of this seller which shows more pictures and full description: http://www.ebay.com/itm/AM-BROADCASTER-TRANSMITTER-HEAR-YOUR-MUSIC-ON-ANTIQUE-AIRLINE-PHILCO-RCA-ZENITH-/131851452425

Rich Powers Part15, Take 2..

I'm curious what you mean by

I'm curious what you mean by "touching the transmitter wife" ;)

Rich Powers Part15, Take 2..

Lol, wire.  I think I'll

Lol, wire.  I think I'll leave the wife alone. She's content with the tv. She looks at me like I'm crazy sitting next to the radio staring at the lighted dial. 

Old time radio

94.1 fm and 1090 AM KWWQ

Serving a tiny portion of leadington

If I had one request it would

If I had one request it would be that it would tune  higher than 1100.  I have found that I get better coverage around 1590 And higher. But other than that I have no complaints thus far.

Old time radio

94.1 fm and 1090 AM KWWQ

Serving a tiny portion of leadington

I was refering to in your

I'm a little comfused on the antenna.. I see two wires which I assume is for power and audio, but see no antenna wire or place to connect one. What am I missing?

 

-- You ought too ask the seller if it can be modified for higher frequencies.

Rich Powers Part15, Take 2..

All three wires come out the

All three wires come out the same hold. Antenna, power, and audio.

Old time radio

94.1 fm and 1090 AM KWWQ

Serving a tiny portion of leadington

But legal to sell?

I have to agree it looks like a very nice transmitter with high quality parts and hand wiring -- reminds me a lot of all the ham radio gear I used to build when I had more time :)

But he can't legally be selling them. Selling an assembled Part 15 transmitter in the USA requires FCC certification. 

I don't want to be the party pooper here, but that's the way it is.

I see no informatiion about certification in the very excellent and thorough description, nor is there required certification information affixed to the transmitter piictured. 

Of course, it's legal for you to use it as long as it meets the technical requirements which it appears to, but it's illegal for HIM to be selling them, putting himself at risk of a fine. 

TIB

That's a shame, hopefully he

That's a shame, hopefully he doesn't run into trouble. It's a fine product 

Old time radio

94.1 fm and 1090 AM KWWQ

Serving a tiny portion of leadington

I noticed that too, but as

I noticed that too, but as Tim mentioned it doesn't have any bearing on the legal use of the transmitter, so on the user end, all is well.

In light of the massive amount of non-legally assembled transmitters consistently being sold and  readily on the open market, it doesn't appear the FCC is particularly concerned about enforcing it. But of course doesn't change the fact that it is indeed illegal to sell, and the seller is engaging in risky business.

 

Rich Powers Part15, Take 2..

It makes me wonder.. When a

It makes me wonder.. When a hobbyist decides to sell something like for example, their own used SStran on ebay..  they are the selling an assembled kit - What is the letter of the law on doing that?

Rich Powers Part15, Take 2..

I've acquired a lot of old

I've acquired a lot of old time radio shows and I must say they sound great. Nice warm sound. 

Old time radio

94.1 fm and 1090 AM KWWQ

Serving a tiny portion of leadington

One is not a business

Of course I can't find the specific FCC rule quickly, but I have it here someplace..

Like most things, it comes down to intent.  A guy who built one transmitter and later sold it as a used transmitter is not breaking the law.

Someone who regularly builds them and sells them is.  If you're building it with the intent of sellling it, it's illegal. If you're building several and selling them, it's not only illegal but it's readily apparent. 

The FCC rules clearly spell this out.  Section 15.201  says:

"Although an operator does not have to obtain a license to use a Part 15 transmitter, the transmitter itself is required to have an FCC authorization before it can be legally marketed in the United States. This authorization requirement helps ensure that Part 15 transmitters comply with the Commission's technical standards and, thus, are capable of being operated with little potential for causing interference to authorized radio communications."

 

Also from the FCC:  

"Hobbyists, inventors and other parties that design and build Part 15 transmitters with no intention of ever marketing them may construct and operate up to five such transmitters for their own personal use without having to obtain FCC equipment authorization. If possible, these transmitters should be tested for compliance with the Commission's rules. If such testing is not practicable, their designers and builders are required to employ good engineering practices in order to ensure compliance with the Part 15 standards.

Home-built transmitters, like all Part 15 transmitters, are not allowed to cause interference to licensed radio communications and must accept any interference that they receive. If a home-built Part 15 transmitter does cause interference to licensed radio communications, the Commission will require its operator to cease operation until the interference problem is corrected. Furthermore, if the Commission determines that the operator of such a transmitter has not attempted to ensure compliance with the Part 15 technical standards by employing good engineering practices then that operator may be fined up to $10,000 for each violation and $75,000 for a repeat or continuing violation.

Operating a prototype of a product that is ultimately intended for market is not considered "personal use." Thus, a party that designs and builds a transmitter with plans to mass produce and market a future version of it must obtain an experimental license from the FCC in order to operate the transmitter for any purpose other than testing for compliance with the Part 15 technical standards. Information on experimental licenses may be obtained from the contact point listed in the Additional Information section of this bulletin. FCC authorization is not required in order to test a transmitter for compliance with the Part 15 technical standards."

There's lots of good information at:   

 

https://transition.fcc.gov/Bureaus/Engineering_Technology/Documents/bull...   

Since his ebay listing says 40 have been sold and three are available, it would be pretty obvious that these are being made for being sold.  And those 40 would just apply to this specific listing. 

But it DOES look like a VERY nice unit, and he can't be making a lot of money on these with those good parts and the labor involved. 

Seems to me there's a legendary story of a antique radio guy building and selling SSTrans or some other similar kit and selling them to old time radio buffs who actually got busted. 

Ah -- here's a long 10 year old thread about it at  

 

http://www.radiodiscussions.com/showthread.php?518708-L-P-Ryan-Low-Power...

 

Most of you have probably already read it. Interesting to note that apparently a maker of certified transmitters filed the complaint. I do not consider that unreasonable. Although many on that old thread do.  AFter all, if someone selling certified transmitters went to the work and expense to have their units certified, why would they not be miffed at someone selling ready to use transmitters who didn't go to the trouble and expense to do it legally?

Anyway, FWIW.  The guys work looks excellent and if I could come up with a reason to have another transmitter for playing around with, I'd be ordering one :)

TIB

 

Excellent info as always Tim.

Excellent info as always Tim.

Sliding slightly off topic to a differenr homebuilt tube transmitter.. You all might have seen this before, but I thought it was real cool.. The compleate description and build instructions are at http://www.radiomuseum.org/forum/hi_fi_am_transmitter.html

Rich Powers Part15, Take 2..

Ah, exactly. and this is

Ah, exactly. and this is where the FCC rules, that have the force of law, get a wee bit fuzzy. 

 

 

Centinel

Seems like the rule is a bit

Seems like the rule is a bit fuzzy on how much would need to be assembled. Even the SSTRAN comes with a few parts "assembled". So the guys with tubes just leave the tubes out of the sockets and the knobs off the case. Problem solved. 

 

 

Centinel

Here's another one....

Interesting.  While I was looking over the one mentioned above, I noticed ebay had inserted images/links to "other items I may be interested in" and one of those was a different tube AM transmitter:

 

http://www.ebay.com/itm/Tube-AM-Broadcaster-With-HD-12AU7-Audio-Pre-amp-...

 

OK, that link looks insane.. wonder if it will work? 

Anyway, seems like both (but especially the second one) have some rules interpretation problems. They both mention a limit of 100 mw *output* (it's input, of course) and this second one claims a 5 meter antenna is OK. So it comes with an 18 footer! Or a 15 footer. Depending on which part of the description you're reading. 

This second one sure looks like one of those vintage Allied units. 

And this other seller also has this one:

 

http://www.ebay.com/itm/Zenith-Designed-AM-Broadcaster-Transmitter-RCA-F...

 

Which is really nice looking. They come with a 25 year warranty!  Wonder who takes over when he dies?  Again, nothing certified -- so although it may be legal to use them, it's not legal to sell them. 

TIB

Tube Tx

Wow, Tim! I like those, especially the last one. Wonder how the range is compared to say, the Talking House...

I like the tube idea. And that last one is beautiful! I need to grab one before he quits selling them! I also wonder about antenna options...non-compliant options of course. Just for testing. I'd put up a 1/2 inch O.D. copper pipe for increased bandwidth.

Doug 

Two words...

Heathkit - Knightkit  

Druid Hills Radio AM-1710- Dade City, FL. Unlicensed operation authorized by the Part 15 Department of the FCC and our Resident Hobby Agent.  

I've been eyeballing these

I've been eyeballing these Tube Transmitters for awhile myself, that is a very sharp looking one Tim posted.

The range is admittedly not very good according to the sellers. I'd suspect with a good antenna setup they would likely be comparable to at least the SSTran 3K in coverage.

Tim is also correct in that these are technically illegal to sell, just like the SSTran, Ramsey, and Spitfire. Much like the ground lead issue, this is one that has historically been largely ignored. (Well, except the FCC actually HAS gone after a few of these kit and homebrew builders.)

I had looked at that sellers

I had looked at that sellers other tube transmitter last night, it's exactly the same transmitter but just in a different housing. I agree it's attractive.

Rich Powers Part15, Take 2..

Tube AM BCB transmitters

I really love the way they look even if they

don't work very well.

I've owned phono oscillators and a carrier

current tube transmitter.   The LPB RC-6A,

which I still have.  This RC-6A has serious 

problems.  I suppose I could strip it and put

a  phono oscillator in the case instead. 

I'm not ready to do that yet, though.  There

are still more things to try that might bring

it back to life.

Vacuum Tubes!

Brooce, Part 15 Hartford CT

NOISE AND STATIC RADIO

Spam Post Deleted

[spam post deleted]

I agree with you Brooce, I

I agree with you Brooce, I just like the look of the tubes! It's kind of like my reel to reel tape deck.. there's an kind of romantic type feel to it.. I recall a big ole radio my dad had and probally still does, it was about the size of a portable tv set and dials on either side, and press down buttons running across the bottom kind of like square piano keys, and on the top right (maybe it was left) of the cloth face it had a green tube that would expand an contract in the shape of an upside down triangle in response to how well you had the station tuned in.

I loved that radio, I think it was german made.. Anyone know what radio I'm talking about?

Rich Powers Part15, Take 2..

Maybe a Grundig with the

Maybe a Grundig with the Magic Eye tube.

Druid Hills Radio AM-1710- Dade City, FL. Unlicensed operation authorized by the Part 15 Department of the FCC and our Resident Hobby Agent.  

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