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tubeguy@myshop.com: Jan 09 08:03PM -0600 >wanted to let people know what I do, and to make them aware of the old >radio programs available over the internet. Listening to Dragnet as I >write, on an FM radio!   Aside from not being AM, I plan to give that link a listen. Sounds like fun listening to those old radio shows. (By the way, those shows were probably all broadcast on AM. FM did not exist at that time).

tubeguy@myshop.com: Jan 09 08:03PM -0600 >is what you want to use.   >Have Fun, >Pat   Thanks to all who replied. I am considering geting one of them ebay mini transmitters, but this is more to see if I can do it with the signal gen. And I have 3 of them to try. I think my Eico 315 is the most suitable though and is my best one.   Yea, I was not thinking when I typed that band number. I was thinking 1650 khz though. (just to avoid other stations from interfering). I have never known any AM stations to exist above 1600. I sort of thought all radios went to 1700, but I guess I was wrong.   Just curious, in what year did they add 1600 to 1700 to the AM band? It does seem to me that a few times I have sent a signal to one of these antique radios and gone above 1600 though, while aligning them. But I suppose it depends on the radio design and how far the tuning cap can go.   For sound quality and for stereo, a FM transmitter would be better, but most of my antique radios are only AM band.   I am not too worried about the FCC coming to "get me". First off, I live in a all metal home. Metal siding and roof. To use my cellphone I have to go outside. Secondly, I live on a farm, and the nearest neighbor is a mile away. So even if it does leak outside a little, only the deer and pesky raccoons who carry pocket radios will pick up my signal. Of course I will take a walk with a pocket radio or use my car radio just to see if it is going beyond my home, and how far.   Interestingly enough, after I posted this, I went to youtube and typed in a few words to search for this. I found that I am not the first person to attempt this. Some guy did it. He found that running a MP3 player right into the signal generator had very weak audio. He then ran the MP3 player into a stereo amp, and connected the amp's output to the signal gen. Doing that, did make a strong signal, but it was rather distorted. However, he connected the 8 ohm speaker output to the signal gen. That alone seems like an overload. I'd be more inclined to use a preamp between the signal gen and the MP3 player. Or use the "tape out" jack from on a stereo amp or receiver. (which is preamp output).   I'll play with it, and see what happens, and post the results, unless the FCC hauls me away and locks me up in some prison in Russia. (Which means I better not play any Russian music over the air). :)

tubeguy@myshop.com: Jan 09 08:04PM -0600 On Mon, 7 Jan 2019 14:55:43 -0600, Fox's Mercantile <jdangus@att.net> wrote:   >kind of modulation bandwidth.   >There's the SSTRAN 3000 which I use. ><http://www.sstran.com/>   I watched a youtube video about this transmitter (actually SSTRAN 5000). I thought this was a good option. I clicked on the URL you posted and it appears they are OUT OF BUSINESS. Their website says something to the extent "No new orders after November xx 2017, and new customers who already paid, will be issued a refund.......   >Another option is the Talking House transmitter. ><https://www.ebay.com/itm/223314565635>   This one is being considered........   >Or, you can roll your own. ><https://antiqueradio.org/transmitter.htm>   Obtaining the inductors (coils) is that hard part for ANY transmitters. I recall haveing a tough time getting them in the late 1960s. I'm sure it's 1000 times harder now. I did get the coils and did build what was called a "Phono Transmitter" in the late 60's. It worked well. Then I took it one step further. I replaced the tube with the horizontal output tube from a TV, and upped the high voltage to around 800V. (The power supply was on a separate chassis).   At that time, I was living in a big city. Using a car radio antenna mounted about 30 ft up on a tree, I put this thing on the air. I never expected the results I got. Several neighbors said their AM radios could not get any stations, except mine. A friend who lives in the suburbs about 15 miles away, said he got my station, clear as a bell.   I got carried away and had it running about 12 hours a day. Had friends act as disk jockeys and we played a lot of the songs that were banned on the regular radio stations. We got a regular studio sound mixer and connected 3 turntables, an 8track and a reel to reel tape player, plus a few microphones. A lot of people loved the station, and wanted to know the location. But we never told that to anyone, knowing this was a pirate station and not legal.   One day a fancy car with all kinds of weird antennas on it began circling my block. I shut off the transmitter immediately. I am very sure it was the FCC, but that tree antenna was well hidden. I planned to move it to another friend's house, but we never did go back on the air. I wish I still had that transmitter. If I did, I'd down power it back to the original design.....   By the way, that thing taught me to respect electricity. I was probably 17 years old. I was tweaking the transmitter when I grabbed the plastic knob on the tuning cap, but my knuckle touched the cap itself, which was live 800VDC. I had a grounded microphone in my other hand. I was sitting on a heavy oak chair. Both myself and the chair were thrown about 12 feet away. The guy who was with me, said I walked around in a daze for a half hour and kept drinking water every few seconds. All I recall, is what looked like a bolt of lightning, when it hit me, and laying on the floor 12 ft from my bench. He said the microphone hit him in the head when I "launched". I sort of recall shutting off the switch that powered my whole bench, right after. That was one scary shock. The worse I ever got.   I did encapsule that tuning cap in a box after that, and modified that cap as well, because I used to get arcing between the plates. The original one was a common 365pf AM radio tuning cap. I remember buying a costly ceramic cap to replace it. Then building a shield around it to avoid any chance of touching it.   When I look back, that whole thing was a lot of fun, aside from that shock. A lot of people were saddened when we went off the air.

tubeguy@myshop.com: Jan 09 08:04PM -0600 On Tue, 8 Jan 2019 10:37:40 -0800, dplatt@coop.radagast.org (Dave Platt) wrote:   >being interfered with. (Commercial licensees have paid $$ for their >licenses, and don't like losing market-share/coverage to pirate >transmitters).   Right now is probably the PERFECT time to operate a pirate station. Since the government is shut down, the FCC is probably not doing much. NO, I am not encouraging this, just commenting......

jurb6006@gmail.com: Jan 09 06:31PM -0800 > Jeff Liebermann wrote: "Try 1650 KHz instead. Kilocycles died 50 years ago."   > Any tech worth their salt understands both. They > express the same value.   OK smartypants, what is -40 Fahrenheit in Centigrade ?

Fox's Mercantile <jdangus@att.net>: Jan 09 08:35PM -0600 > Aside from not being AM, I plan to give that link a listen. Sounds like > fun listening to those old radio shows. (By the way, those shows were > probably all broadcast on AM. FM did not exist at that time).   FM radio was assigned the 42 to 50 MHz band of the spectrum in 1940. But then WWII happened. After the war, on June 27, 1945 the FCC made its decision final and allocated one hundred FM channels from 88–108 MHz.   The "Golden Age of American radio", period lasting roughly from 1930 through the 1940s, However he last network radio dramas to originate during American radio′s "Golden Age", Suspense and Yours Truly, Johnny Dollar, ended on September 30, 1962.   -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

Fox's Mercantile <jdangus@att.net>: Jan 09 08:48PM -0600 > I have never known any AM stations to exist above 1600.   It is currently 530-1700 KHz. Originally, in 1923, it was 540-1340 KHz.     -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

"pfjw@aol.com" <peterwieck33@gmail.com>: Jan 10 05:16AM -0800 > > Any tech worth their salt understands both. They > > express the same value.   > OK smartypants, what is -40 Fahrenheit in Centigrade ?   The same. I am bi-temperate having lived under metric and non-metric systems.   Peter Wieck Melrose Park, PA

"pfjw@aol.com" <peterwieck33@gmail.com>: Jan 10 05:28AM -0800 On Wednesday, January 9, 2019 at 9:48:36 PM UTC-5, Fox's Mercantile wrote: > Jeff-1.0 > WA6FWi > http:foxsmercantile.com   I have a 1930s-vintage Coronado chairside that looks like this:   http://antiqueradios.com/gallery/main.php?g2_itemId=29062 That calls itself a dual band radio, being AM & Police/Aircraft. It is a single-band radio with the AM bandwidth expanded.   The dial goes from 530 to 1790. Police band back in the day was 1714. I have not been able to pin down Aircraft, but I expect somewhere below 1790.   The radio is also unusual in that it had an acorn bias-cell - now replaced with a 1.5V AAA. Plays nicely.   Peter Wieck Melrose Park, PA

Look165 <look165@numericable.fr>: Jan 09 05:43PM +0100 Just clean with a Q-tip and that's all. Cleaning tape is usefull.

tabbypurr@gmail.com: Jan 09 11:03AM -0800 On Wednesday, 9 January 2019 16:12:46 UTC, Terry Schwartz wrote: > > > acetone on the heads?   > > Use a cleaning tape or the like . Chemicals and liquids can harm rollers and other plastic / rubber parts . Alcohol will dry out the oils in plastics and rubber , causing them to harden . Acetone will tend to dissolve these materials .   > All those materials are 19 years older than when this topic was initiated.... So yeah, I bet they're dried out.   cleaning tapes are almost hopeless anyway. Wet cleaning is the only effective option.   Don't use rubbing alcohol, it contains oil. Vodka is fine. Clean the pinch wheels as well. All must be bone dry before putting a tape in.     NT

The Real Bev <bashley101@gmail.com>: Jan 09 08:12PM -0800 > effective option.   > Don't use rubbing alcohol, it contains oil. Vodka is fine. Clean the > pinch wheels as well. All must be bone dry before putting a tape in.   The heads are metal. No worries about hardening. Who told you there was oil in rubbing alcohol? It's alcohol and water. Period.     -- Cheers, Bev "I've learned that you can keep puking long after you think you're finished." -- SL

gregz <zekor@comcast.net>: Jan 10 08:07AM >> pinch wheels as well. All must be bone dry before putting a tape in.   > The heads are metal. No worries about hardening. Who told you there was > oil in rubbing alcohol? It's alcohol and water. Period.   Heads have some insulating material imbedded. Real rubbing alcohol is supposed to have oil to prevent skin drying too much. Most don't. Isopropyl or ethyl cleans heads.   Greg

tabbypurr@gmail.com: Jan 10 12:31AM -0800 On Thursday, 10 January 2019 04:12:57 UTC, The Real Bev wrote: > > pinch wheels as well. All must be bone dry before putting a tape in.   > The heads are metal. No worries about hardening. Who told you there > was oil in rubbing alcohol? It's alcohol and water. Period.   I forget the official standard for it, but it contains rather more than water & alcohol. Looked it up last year.     NT

Look165 <look165@numericable.fr>: Jan 10 10:18AM +0100 The body of the head is made of molded resin. The magnetic element is made of polished folded iron.(try to look with a microscope). I go on saying that a good quality cleaning head is useful. Don't forget to adjust the azimuth setting at the end.     gregz a écrit le 10/01/2019 à 09:07 :

bruce2bowser@gmail.com: Jan 10 02:58AM -0800 And I suppose you have to pause your 25/hr 8-day-a-week smoking habit during this time too, right?

etpm@whidbey.com: Jan 09 09:38AM -0800 I see really expensive audio output and power transformers for sale as well as cheap ones. And lots of folks really want older ones because they are better than the new crop. So what is the difference? It must be some sort of physical attribute. The way they are wound, insulation, etc. Is there a way to tell using just an oscilloscope? I'm just curious. I am very happy with the way my tube amp sounds. Thanks, Eric

gregz <zekor@comcast.net>: Jan 10 08:13AM > curious. I am very happy with the way my tube amp sounds. > Thanks, > Eric   Frequency response delivering full power is what I think. Some trick winding process is likely to cost more.   Greg

tubeguy@myshop.com: Jan 09 08:03PM -0600 Most of my vintage testers have those old style 5/8" screw on MIC connectors. I have considered changing all of them to BNC and I see many people do this, but I really dont feel like opening each tester to do this, plus I kind of like keeping vintage gear original.   I have some probes with the MIC connectors, but there are times I'd like to use a probe with a BNC on my vintage testers.   My idea is to simply make a few adaptors. I have several of the old MIC connectors, and I have a bunch of the chassis mount BNC connectors (which I believe is called the "female"). But I am not seeing any INLINE female BNC connectors. If I could find these female INLINE ones, I'd simply take a 6" piece of coax, and put the MIC connector on one end and the BNC on the other. Making 2 or 3 of these should suffice.   Has anyone seen any female INLINE BNC connectors to buy? Or, is there another method to accomplish this?   Yes, I could solder on the chassis type BNC connectors, but they would lack shielding at the connector.

Fox's Mercantile <jdangus@att.net>: Jan 09 08:25PM -0600 > Has anyone seen any female INLINE BNC connectors to buy? > Or, is there another method to accomplish this?   You can use these: <https://www.ebay.com/itm/183118810685>   Or you can do what I did. 1. Remove spring from connector. 2. Drill out connector back with 11/32" drill. 3. Tap connector shell using 3/8-32 tap. 4. Solder #16 wire to solder cup on back of BNC female. 5. Stick wire through connect grommet in Amphenol connector. 6. Screw BNC into connector shell. Tighten. 7. Solder wire to Amphenol connector grommet. 8. Cut wire, smooth with file.   Presto! Instant, sort of, Amphenol Microphone to BNC adapter.   -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

tubeguy@myshop.com: Jan 09 08:09PM -0600 On Mon, 07 Jan 2019 14:20:44 -0800, Jeff Liebermann <jeffl@cruzio.com> wrote:     >A few questions:   >1. Which knob? ><https://c1.staticflickr.com/4/3834/11055642634_e5daa78fe7_b.jpg>   The CALIBRATED one with numbers on it.   >brass center insert? I haven't seen too many knobs without this brass >insert as threading the plastic doesn't last very long on small >diameter knobs.   No brass parts, the set screw is in plastic, part of the piece that fits on the 1/4" shaft is broken away (opposite set screw).   >centered. Instead of trying to totally drill out the brass insert, I >used a smaller drill (or end mill) that left a thin brass annular >ring. I removed that with a pair of pliers.   Like I said, there is no brass in it. not the best quality knob in my opinion..... even if it is 50 years old.........

tabbypurr@gmail.com: Jan 09 10:59AM -0800 > what is going out of the receiver/amp to > the record deck.   > From my own experience.   Other way round. Confusion can come from the fact that on a lot of amps the selected input is connected directly to the tape output*, thus one can always use 'tape output' as an unswitched input. I say always... some amps won't work this way since there are buffers in the way, and they don't pass signal backwards.   *Phono inputs are of course preamplified first.     NT

thekmanrocks@gmail.com: Jan 09 12:30PM -0800 tabb...@gmail.com wrote: "Other way round."   Nope. I hooked the thing up via literal interpretation, and got no playback audio from tapes, and nothing recorded to blanks.   Once I reversed them, like I said, everything worked as it was expected to.   And as can be seen from Terry's testimony some posts back, I'm not the only one experiencing gear labeled counterintuitively to how it was supposed to be hooked up.   You weren't there in either of our cases, so you can't refute either of our experiences.

Chuck <ch@dejanews.net>: Jan 09 02:38PM -0600 On Tue, 8 Jan 2019 16:35:58 -0800 (PST), dansabrservices@yahoo.com wrote:   >> flipped both RCA pairs around, Voila, >> everything was fine.   >I won't argue your results, but with 35 years of repairing audio gear, I have not seen one yet that has that property. The in/out label on any gear is usually for that particular unit. The same exists on tape machines. There are input and output jacks there as well. The "output" jack on the tape should be activated when the tape is in play mode, thus is an output. Me either. Audio-video tech for 30+ years.

John-Del <ohger1s@gmail.com>: Jan 09 03:27PM -0800 > to how it was supposed to be hooked up.   > You weren't there in either of our cases, so you can't refute > either of our experiences.     No one is calling you a liar, but after nearly 50 years repairing consumer electronics as a career, I've never seen one wired like that. To me, this means the examples you cite are aberrations or at least a very small percentage of the units in service. They could have been wired that way intentionally or maybe the jacks or TM switch were miswired. It's also possible the rear panel was simply silk-screened incorrectly or a revised version was released with the previous version's back panel.   As I pointed out above, the other possibility is that the INs and OUTs were prefaced by "connect to", which changes the context entirely. I recall some low end packaged component systems that did not use universal nomenclature, but had connection "instructions" on the back panel (ie: connect to tape deck output).

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