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tubeguy@myshop.com: Feb 19 11:13PM -0600 In the 1960s the pocket radios hit the market and were sold everywhere. I have not opened one of them in years, but I recall the transistors used in them did not look like more modern types. They had a small metal can. Just a straight sided metal can, shaped like modern capacitors, but bare metal. Some had colored dots on them to identify the leads too.   First, I am thinking that they were geranium types. Is that correct?   Second, I have a very old GE transistor manual (edition 2) (PDF). No where in there does it mention the case style of them. What is the case style?   Seems those type of transistors came and went quickly. I assume they were the first generation of transistors.   Shortly after, I recall seeing a lot of metal cases that were shaped more like a hat, with a brim. Those too vanished. And I recall seeing some of the hat shaped types with a point sticking out of the top. I always wondered what that point was for???

Allan <a_r_macdonald@hotmail.com>: Feb 20 12:34AM -0800 > more like a hat, with a brim. Those too vanished. And I recall seeing > some of the hat shaped types with a point sticking out of the top. I > always wondered what that point was for???   Sounds like BC108 series the tab idenified the emitter I think.

tabbypurr@gmail.com: Feb 20 12:42AM -0800 > can. Just a straight sided metal can, shaped like modern capacitors, but > bare metal. Some had colored dots on them to identify the leads too.   > First, I am thinking that they were geranium types. Is that correct?   germanium yes.   > Second, I have a very old GE transistor manual (edition 2) (PDF). No > where in there does it mention the case style of them. What is the case > style?   There was TO1, but there were others   > Seems those type of transistors came and went quickly. I assume they > were the first generation of transistors.   no, just the 1st generation cheap enough to go into pocket radios   > Shortly after, I recall seeing a lot of metal cases that were shaped > more like a hat, with a brim. Those too vanished. And I recall seeing   More than one case type, eg TO39   > some of the hat shaped types with a point sticking out of the top. I > always wondered what that point was for???   to kill your opponents of course.     NT

Look165 <look165@numericable.fr>: Feb 20 10:47AM +0100 I would say it is ACxxx or AFxxx ; they were cased in metal can and sealed with glass. The coloured point was indicating the collector. OCxx were cased in black glass with golden leads. The so called point (white, red, green or yellow) on top was indicating the gain range like, A, B, C today. The second one on bottom was indicating the collector.   All were Germanium transistors (take care, ||Vbe||=0.3V). Then came the 2N4xx.

Phil Allison <pallison49@gmail.com>: Feb 20 02:01AM -0800 tub...@myshop.com wrote:   . . > can. Just a straight sided metal can, shaped like modern capacitors, but > bare metal. Some had colored dots on them to identify the leads too.   > First, I am thinking that they were geranium types. Is that correct?   ** Yep - made by the Japanese and many others.     http://oldtube.com/2N408-RCA-used-1pc.jpg       > Second, I have a very old GE transistor manual (edition 2) (PDF). No > where in there does it mention the case style of them. What is the case > style?   ** TO1       > Shortly after, I recall seeing a lot of metal cases that were shaped > more like a hat, with a brim. Those too vanished.   http://oldtube.com/2N508-ETCO-Au-2pcs.jpg     > And I recall seeing > some of the hat shaped types with a point sticking out of the top. I > always wondered what that point was for???       ** You are always missing the point .....   See here for pics of a great many old semis.   http://oldtube.com/Oldtube-semiconductors.htm       .... Phil

Wond <gboot.phil@gmx.com>: Feb 20 03:32PM On Wed, 20 Feb 2019 02:01:51 -0800, Phil Allison wrote:     > ** You are always missing the point .....   > See here for pics of a great many old semis.   > http://oldtube.com/Oldtube-semiconductors.htm   Thanks for the link, Phil. What- no CK722!

"Rod Speed" <rod.speed.aaa@gmail.com>: Feb 20 05:49PM +1100 "micky" <NONONOmisc07@bigfoot.com> wrote in message news:oslp6ehjgeororp691fq6rk5bknptqiej8@4ax.com... >>only with the old radios tho, not modern digital ones.   > Digital radios won't work here. They all afaik > have a separate momentary-on on/off switch.   Not all of them do, most obviously with car radios.     >>> This is common, I assume.   >>No it isnt.   > I thought I had at least two radios like this.   Looks like you have fluked a couple of duds. None of my analog radios do that.     > I know some radios have an AFC switch, so you can get weak stations that > are close to strong stations, but if there is no AFC switch, I thought > all FM radios have AFC anyhow.   Normally the analog ones do, not needed with digital ones.   > even though TV sound in the 50's and until digital is supposed to be > FM and the radio was AM. Nonetheless, I turned on a TV and found > the channel it was receiving.   Yeah, you can decode FM with an SSB receiver.   > frequency. Finally after an hour or two, I reached the end of the band. > IIRC I switched to the bottom of the next higher band but I couldn't > find the same transmission.   Likely it was an intermodulation that you were receiving and the signal it was intermodulating with was what was drifting that dramatically.   > Yes, the thing was 30 years old but it was certainly well-designed.   Yeah, very decent designs.   > I still have the radio and I've only had to replace > the AC filter capacitors. Everything else still > works, even though it's about 85 years old now.   Yeah, they do last well.

tabbypurr@gmail.com: Feb 20 12:48AM -0800 On Wednesday, 20 February 2019 03:51:29 UTC, rbowman wrote: > > what makes radios drift from the proper tuning?   > How old and crappy are your radios? Have you made it up to a > superheterodyne or are you still in the regenerative era?   My 1930s regen doesn't drift after half an hour. But don't look at it sideways.     NT

tabbypurr@gmail.com: Feb 20 12:51AM -0800 On Wednesday, 20 February 2019 04:40:06 UTC, micky wrote:   > still have the radio and I've only had to replace the AC filter > capacitors. Everything else still works, even though it's about 85 > years old now.   AM receivers can receive FM due to a phenomenon called slope detection. It's hardly ideal but can be done. If they can tune to the right frequency.     NT

Peeler <troll@trap.invalid>: Feb 20 10:04AM +0100 On Wed, 20 Feb 2019 17:49:56 +1100, cantankerous trolling senile geezer Rot Speed blabbered, again:   >> I thought I had at least two radios like this.   > Looks like you have fluked   Looks like you found another simpleton who hasn't yet realized what's the matter with you, you fucked up senile Ozzie troll! <BG>   -- Richard addressing Rot Speed: "Shit you're thick/pathetic excuse for a troll." MID: <ogoa38$pul$1@news.mixmin.net>

devnull <devnull@127.0.0.1>: Feb 20 06:21AM -0500 On 2/19/19 11:27 PM, micky wrote: > BTW, I've been on 3 trips in the last 2 years totaling 160 days and no > one has bothered my house at all. I just want to keep it that way.       Life is a constant battle of keeping burglars out of my house and democrats out of my paycheck. Democrats suck!

"pfjw@aol.com" <peterwieck33@gmail.com>: Feb 20 06:10AM -0800 On Tuesday, February 19, 2019 at 6:58:37 PM UTC-5, micky wrote: > what makes radios drift from the proper tuning?   Depending on the vintage of the device:   Heat and vibration are the primary culprits. Followed by temperature differences - that is, on a battery set or a low-volt portable tube set, heat from the electronics is not a factor. But a 10-degree change in ambient temperature can cause drift.   Then, of course, it can be changes in the time-of-day and environmental effects, local sources of interference and similar. At our summer house, FM is problematic during the day (we are in a valley with at least two mountain ridges between us and the nearest transmitter), but crystal clear at night from several stations. Yes, I know FM is line-of-sight, I am only reporting what is the actual case.   "Modern" Digitally tuned devices should not drift at all. And perhaps you should target such devices for your needs while you are away.   Peter Wieck Melrose Park, PA

rbowman <bowman@montana.com>: Feb 20 08:03AM -0700 On 02/19/2019 09:07 PM, danny burstein wrote: >> superheterodyne or are you still in the regenerative era?   > Me, I'm still waiting to upgrade to using a stainless > steel razor blade for mine...   Probably won't work. A Gillette Blue Blade is best but if you are a manly man a rusty blade or one you've heated with a torch to get a layer of oxide will do it.

micky <NONONOmisc07@bigfoot.com>: Feb 20 10:32AM -0500 In alt.home.repair, on Tue, 19 Feb 2019 23:17:21 -0500, Ralph Mowery   >Just turn the radio on and let it play for half an hour before putting >it on a timmer.It may come on off frequency ,but as it warms up it >should drift to the station.   That sounds good.   Thanks everyone.

Look165 <look165@numericable.fr>: Feb 20 11:02AM +0100 First : check the shield of your antenna cable and the plugs. Normally telecom use a separate frequency band and your TV has an AGC. Me, I should contact a technician of this telecom center to see what can be done.   Peter Jason a écrit le 20/02/2019 à 05:53 :

John-Del <ohger1s@gmail.com>: Feb 20 04:27AM -0800 On Tuesday, February 19, 2019 at 11:53:21 PM UTC-5, Peter Jason wrote: > Are there special filters for this sort of thing, > and if not how should I frame a complaint?   > .   Interference? I don't know how you can tell that with a digital tuner. Pixelation, drop outs, freezes, and no signal indications usually mean borderline signal to noise ratio.   Get a better antenna, add an amplifier, and carefully redirect it. If your TV has a signal level meter (unusual), you can use that. Many ATSC stand alone boxes did have a signal level utility which is helpful in seeing how much signal you have.

Fox's Mercantile <jdangus@att.net>: Feb 20 07:14AM -0600 On 2/20/19 6:27 AM, John-Del wrote: > Interference? I don't know how you can tell that with a digital tuner.   You can't.   It's like Hatlow's "They'll do it every time." A bunch of neighbor's pointing at the local amateur radio guy. Among other comments, "I hear he even interferes with Doc's diathermy machine.   -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

tubeguy@myshop.com: Feb 19 11:14PM -0600 I have a small solid state amplifier (receiver) and speakers which I use for my computer sound. It sounds good. Much better than those amplified "computer speakers".   But I have determined that it is never shut off. When I push the ON-OFF switch, the sound stops and the pilot LED goes off.   The switch is NOT on the line cord, but somewhere inside the circuit. (No schematic available). I have determined that it's never shut off completely. When it's turned off, if I put my ears right to the speaker, I can still hear a very slight hum. My kill-a-watt meter shows it's always drawing .05 amps when it's turned off.   I'm sure that small power draw only costs pennies each month for the electric, but its still a waste of power, and I prefer ALL electronics are completely shut off during lightning storms.   What the heck kind of a circuit would be used to turn it off, but still leave it semi-powered? And why????   For now, I put it on a power strip, but that strip is not always shut off, when I am recharging my computer (laptop) battery. I am probably going to put one of those inline line cord switches on it. But then I will have to turn on BOTH the line cord switch and the built in one. (Not that this is a huge problem).   I dont understand why anything would be designed this way. There is no remote control, so it's all senseless.... and poor design. My only guess is that it stays powered so it can retain radio stations in memory. (Stereo Digital Synthesize Tuner with push button presets). But I never use the radio part of it anyhow.   If I could find a schematic, I would try to modify the internal switching. But I have tried to get one, and they do not exist. (This receiver is probably from the 80s).   If it was not for the fact that it has great sound, and a built in equalizer, I'd probably just replace it. Low powered solid state receivers or amps are easy to find and cheap to buy.

Rheilly Phoull <rheilly@bigslong.com>: Feb 20 01:23PM +0800 > If it was not for the fact that it has great sound, and a built in > equalizer, I'd probably just replace it. Low powered solid state > receivers or amps are easy to find and cheap to buy.   Disconnect the switch and use it to interrupt the dc supply?

tabbypurr@gmail.com: Feb 20 12:45AM -0800 > If it was not for the fact that it has great sound, and a built in > equalizer, I'd probably just replace it. Low powered solid state > receivers or amps are easy to find and cheap to buy.   A low voltage switch is cheaper than a mains one. A tactile or membrane switch is even cheaper.   You didn't tell us the power factor. If 1, 0.05A would cost about 5c a year if on 24/7/365. If the pf is 0, it'll cost nothing. It's not worth fitting a mains switch. If it had one it would not be worth operating it.     NT

"pfjw@aol.com" <peterwieck33@gmail.com>: Feb 20 04:13AM -0800 Brand and age would be quite useful. Back in the days when solid-state "high-powered (+/-60 watts)" amplifiers were new, a fair number of manufacturers would maintain a low-level current through their equipment to avoid thumps and bangs during turn-on - that could damage speakers, again back in the day.   Such manufacturers included:   AR Dynaco Scott KLH and others.   That you are getting a 5-6 watt draw is a bit higher than typical, but within the range. An added benefit is that this process 'kept the capacitors wet' as AR described it, helping their longevity in theory.   Peter Wieck Melrose Park, PA

tabbypurr@gmail.com: Feb 20 12:33AM -0800 On Wednesday, 20 February 2019 01:06:16 UTC, Peter Jason wrote:   > Is there a fix; is it a loose connection, dust or > grit in the works? Should I just flush it out.   > Otherwise the radio works well.   Sometimes all one need to is twiddle the control back & forth a dozen or 2 times. Sometimes it also needs some cleaner sprayed into the pot. Sometimes that doesn't fix it & it needs its terminals resoldering.     NT

tabbypurr@gmail.com: Feb 20 12:33AM -0800 On Wednesday, 20 February 2019 08:33:18 UTC, tabby wrote:   > > Otherwise the radio works well.   > Sometimes all one need to is twiddle the control back & forth a dozen or 2 times. Sometimes it also needs some cleaner sprayed into the pot. Sometimes that doesn't fix it & it needs its terminals resoldering.   > NT   and rarely the track is worn out.

Look165 <look165@numericable.fr>: Feb 20 10:55AM +0100 Generallly, it comes from a bas contact between the cursor aand the resistive track (dust or oxyde). It can also come from a miscontact between this track and the connecting pad or a "dry solder". First step : re-solder everything. Second step : use some KF or equivalent in large quantity inside (through the opening of the leads).   Peter Jason a écrit le 20/02/2019 à 02:06 :

tabbypurr@gmail.com: Feb 20 12:24AM -0800 On Tuesday, 19 February 2019 20:13:45 UTC, Phil Allison wrote:   > > Both of those are way above audio, which only extends to 20kHz.   > ** While the audible range extends to just a little over 20kHz this has NOTHING to do with the frequencies regularly encountered in *audio electronics*.   that is stating the obvious, and we've already covered that.   > You are making a common and BIG mistake !!!   > A scope suitable for audio electronics needs a BW of at least 10MHz, preferably 50MHz and good waveform resolution - which counts out all the 8 bit "digital" toys being offered today.   > .... Phil   I've asked you to provide a basis for this claim.     NT

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