Why should someone replace ALL the capacitors on old Tube eq

[Jim Mueller]

On Sat, 04 Feb 2017 04:28:09 -0600, oldschool wrote:

On Fri, 3 Feb 2017 22:05:48 -0000, "Benderthe.evilrobot"
Benderthe.evilrobot@virginmedia.com> wrote:


True. But the reason to replace them ALL is that if you only replace
the one(s) causing a problem, another will fail later, then another
still later. It is much easier to do them all at once than to have to
repair the same unit over and over as they fail one after another.
Been there, done that.

So have I.


I can totally understand what you are saying. However, I am not so sure
about whether I would want to replace all of them in certain parts of a
radio or tv. Here are my thoughts on this.

Lets take my Hallicrafters SX-99 (which I paid for but dont have yet).
That radio is 62 years old. (made in 1955). The seller said it works
fine, (and I was sent a video of it working. I did detect a very slight
hum. (But the video's audio is not the greatest).

So, as soon as I get it and play around with it, I will replace the
electrolytics in the power supply and any other 'lytics (if there are
others). Even if there is no hum, I'd replace them, just based on age.

However, this is a working radio. I ask myself if I really want to
replace all the other (small) caps. [Then I say to myself.... if it
works, dont fix it].

But, I know there are caps in specific circuits more likely to fail,
than in other circuits. Those would be caps connected to the high plate
voltages, especially at the audio output tubes and in the power supply.
I also know that if those short out, they can damage other parts, such
as tubes, resistors, and more. So, I would likely consider replacing
those. I might even consider replacing ALL the caps in the power supply,
and all audio stages, and feel safe doing that, since those caps are not
real critical as far as affecting the overall performance of the radio,
even if the new caps are a little different in their capacitance.

Where I do NOT feel comfortable changing them, are in all RF and IF
stages. The reason is that I know that a cap/coil circuit plays a big
part in the inductance, which affects the radio alignment. I am not
equipped to align the radio coils, and would prefer to leave them alone,
as long as the radio is getting good reception.

I also know that those RF and IF stages do not operate on as high
voltages as do the audio output stages. So, once again, I ask myself,
"Do I really want to risk throwing this radio out of alignment, when
it's working fine, and knowing those caps are not as likely to fail".

I answer myself "Probably not".... (As long as the radio is working
well, dont screw up a good thing.... Then too, if the caps in those
circuits are .05 or .003, I WANT a .05, not a .047. (And it seems that
.05 is no longer made).

So, if I'm satisfied with the performance of this radio, I will replace
the 'lytics regardless. I may also replace all caps AFTER the volume
control, as well as all caps in the power supply. But I will likely NOT
touch any caps in the RF and IF stages.

That's my thinking on all of this right now. Not just for this radio,
but anything..... Now, if it were simply an audio amplifier, I'd likely
replace all the caps, because audio is not all that critical.

I think that there is a misunderstanding here. The statement to replace
all the capacitors actually means all the electrolytic and paper
capacitors. Usually ceramic and mica capacitors are still good and
nobody replaces those unless they are proven to be bad.

The paper capacitors in the IF and RF stages need to be replaced even if
the radio "works". Leaky capacitors change the voltages on the tubes
causing them to work at less than their best performance. Also, these
capacitors are used as supply bypasses and AVC filter capacitors. They
do not affect the alignment of the set; the ceramic and mica capacitors
may. Their value is not particularly critical; pick the closest modern
value.

Consider the value issue. If the radio has a .05 uF, 20% capacitor in
it, its actual value can be anywhere from 0.04 uF to 0.06 uF. A modern
0.047 uF 10% capacitor can be between .0423 uF and 0.0517 uF. So the
0.047 uF capacitor can be closer to 0.05 uF than the old one marked with
that value.

As for life expectancy, there was a time in the late '50s and early '60s
when both paper and plastic film capacitors were used. The paper
capacitors I have from that period are universally bad while the plastic
film ones are almost always good. Plastic film has passed the test of
time.

As for what type of plastic film to use, polyester (AKA Mylar) is the
cheapest and has the poorest performance. But it is still better than
the paper capacitors of old so it is suitable for use just about anywhere
a paper capacitor was formerly used. Polycarbonate (no longer made) and
polypropylene are better but more expensive. Polystyrene capacitors are
also very good and inexpensive but are usually seen only in small values
and are frequently not seen at all. They also have the problem that they
melt at lower temperatures than other plastic capacitors and solvents
dissolve them. Still, within their limitations, they are excellent.

--
Jim Mueller wrongname@nospam.com

To get my real email address, replace wrongname with dadoheadman.
Then replace nospam with fastmail. Lastly, replace com with us.

 

[Jim Mueller]

Wow, this thread has really taken off. It's almost like the old days of
Usenet!

--
Jim Mueller wrongname@nospam.com

To get my real email address, replace wrongname with dadoheadman.
Then replace nospam with fastmail. Lastly, replace com with us.

 

On 04 Feb 2017 23:46:23 GMT, Jim Mueller <wrongname@nospam.com> wrote:

On Sat, 04 Feb 2017 15:26:31 -0600, oldschool wrote:

On 03 Feb 2017 02:13:07 GMT, Jim Mueller <wrongname@nospam.com> wrote:

The old electrolytic capacitors you are talking about don't sound like
the oil filled variety. Indeed, if they are electrolytic, they aren't
oil filled. Oil filled capacitors aren't polarized and many of them are
good today. They were the high quality capacitors used in military and


I always thought those were oil filled, but I see I was wrong. I looked
on the web too, and it appears that most of them were filled with a
boric acid solution, which is not really harmful. They all had the tiny
vent hole in the top, and had a large threaded mounting on the bottom,
which required a sizable nut.

It's been years since I touched one of them. I only remember (vividly)
getting sprayed by one of them many years ago. It was boiling hot and it
hurt like hell. After that incident, I just replaced them before I even
pluggd in anyting that had that type of cap. (Or put a soup can over
them temporarily) They were probably the worst caps ever made.

Here is a pic I found online.
https://antiqueradio.org/art/Midwest18-3621.jpg

Progress is incremental. Those capacitors had major advantages over what
came before. The "dry" electrolytics that followed them had further
advantages. That's how things go.

I know the dry 'lytics were better, I have to ask what came before these
wet ones with the vent hole? I really dont know...

One thing I liked about those wet ones was the threaded nut on the
bottom. Very easy to install and remove! Those twist tabs on the dry
caps in the metal cans tended to break off quite easily, if the cap was
being removed to be reused elsewhere, and if one was soldered, it was
even harder. (generally one was soldered).

 

On Sat, 4 Feb 2017 17:05:43 -0600, Foxs Mercantile <jdangus@att.net>
wrote:

On 2/4/2017 1:49 PM, oldschool@tubes.com wrote:
Back then, I used a lot of orange drops as replacements and
I never had problems with them. I will say that I did not
always like the fact that their wires come out of the bottom,
since for non-circuit board applications, they were a little
clumsy to fit into some places, versus the tubular caps with
wires on the ends.

They are good parts. A bit over priced however. And yes, radial
leads instead of axial. Can be an issue when you're replacing
axial lead parts.

I wonder why they dont make them both radial and axial? I'd think that
it's just a matter of rerouting the wires from the same innards.

 

On 05 Feb 2017 00:21:42 GMT, Jim Mueller <wrongname@nospam.com> wrote:

I think that there is a misunderstanding here. The statement to replace
all the capacitors actually means all the electrolytic and paper
capacitors. Usually ceramic and mica capacitors are still good and
nobody replaces those unless they are proven to be bad.

The paper capacitors in the IF and RF stages need to be replaced even if
the radio "works". Leaky capacitors change the voltages on the tubes
causing them to work at less than their best performance. Also, these
capacitors are used as supply bypasses and AVC filter capacitors. They
do not affect the alignment of the set; the ceramic and mica capacitors
may. Their value is not particularly critical; pick the closest modern
value.

I hear you.....

Consider the value issue. If the radio has a .05 uF, 20% capacitor in
it, its actual value can be anywhere from 0.04 uF to 0.06 uF. A modern
0.047 uF 10% capacitor can be between .0423 uF and 0.0517 uF. So the
0.047 uF capacitor can be closer to 0.05 uF than the old one marked with
that value.

OK. That makes sense...

As for life expectancy, there was a time in the late '50s and early '60s
when both paper and plastic film capacitors were used. The paper
capacitors I have from that period are universally bad while the plastic
film ones are almost always good. Plastic film has passed the test of
time.

As for what type of plastic film to use, polyester (AKA Mylar) is the
cheapest and has the poorest performance. But it is still better than
the paper capacitors of old so it is suitable for use just about anywhere
a paper capacitor was formerly used. Polycarbonate (no longer made) and
polypropylene are better but more expensive. Polystyrene capacitors are
also very good and inexpensive but are usually seen only in small values

I see where this can get confusing. I'll consider the polyester (AKA
Mylar), but for the small cost difference, I'd probably prefer the best.
It looks like polypropylene would be that choice.

Do you have any brand names to recommend for these types?
(I will be buying online, there are no electronics stores around here).

and are frequently not seen at all. They also have the problem that they
melt at lower temperatures than other plastic capacitors and solvents
dissolve them. Still, within their limitations, they are excellent.

Dont you mean they melt at a *HIGHER* temperature? I cant imagine how
something could melt at a low temp?

Upon reading a URL that somone posted on here, I see where the
audiophliles say that some caps have better sound quality, than others.
On a SW radio, I'm not really looking for "precision sound", but more so
for best performance from the signal coming from the antenna to the
speaker. And while some (or most) of these newer types of caps are made
to be used with modern gear, containing semiconductors, which are the
best choice for old tube stuff. I would think that the caps should mimic
the old paper caps, because that is what these circuits were designed to
use. I know the values of caps are the capcitance (in MF or MMF) and the
voltage. But I know there are other factors that I know nothing about.
Someone mentioned tempco (is that what I read?) in another message in
this thread. What the heck is that?

Either way, I do believe the caps should be similar to the original ones
to work properly. Just made from better materials.

--
Jim Mueller wrongname@nospam.com

 

On 05 Feb 2017 00:42:19 GMT, Jim Mueller <wrongname@nospam.com> wrote:

Wow, this thread has really taken off. It's almost like the old days of
Usenet!

I miss those days. The majority of newsgroups are either dead or filled
with morons or off topic political based fighting and name calling these
days. There were many worthwhile newsgroups that I used to enjoy, and I
wont even go there anymore.

I cant understand where everyone went. I know almost everyon has an
account with that miserable facebook these days (except me), but I cant
say I have ever seen any useful discussions on FB. For the brief time I
did connect to FB, what I saw was just a lot of links to websites
dealing with world affairs, and lots of rude comments about them. Or
pictures of people when they were drunk, with more rude comments.... Not
to mention the 20 or more ads on each page. The day when FB becomes the
entire internet, is the day I pull the plug. (And actually I cant even
use FB if I did want to. My only affordable internet access is still
dialup, because that's all there is in this rural area where I live, and
bloated websites like FB and most of the news media sites wont even load
anymore).

 

[Foxs Mercantile]

On 2/4/2017 7:25 PM, oldschool@tubes.com wrote:

Do you have any brand names to recommend for these types?
(I will be buying online, there are no electronics stores
around here).

I get mine from here:
<http://www.tuberadios.com/capacitors/>




--
Jeff-1.0
wa6fwi
http://www.foxsmercantile.com

 

[Bill Burns]

On 2/4/2017 8:49 PM, oldschool@tubes.com wrote:

On 05 Feb 2017 00:42:19 GMT, Jim Mueller <wrongname@nospam.com> wrote:

Wow, this thread has really taken off. It's almost like the old days of
Usenet!

I miss those days. The majority of newsgroups are either dead or filled
with morons or off topic political based fighting and name calling these
days. There were many worthwhile newsgroups that I used to enjoy, and I
wont even go there anymore.

Hard to believe r.a.r+p dates back to September 1994. I was one of the
founding members under my email address at the time, billb@savvy.com

http://fmamradios.com/RESULT-rar+p.txt

-- Bill

 

[Nick Danger]

On 2/4/2017 4:58 PM, Nick Danger wrote:
True in my case too. I also used them along with 88 mh toroidal
telephone loading coils to make Mark / Space filters for radio
teletype decoders --and the orange drops were very stable. (I
know, I'm dating myself in this day and age of software/sound
card RTTY decoders).

On 2/4/2017 6:03 PM, Foxs Mercantile wrote:

You and me brother. You and me. ;-)
As a side note, I'm still playing with RTTY and using a real
machine. A Lorenz Lo-15c. ;-)

Interesting...but I never had what I presume to be a European machine.

Started with a Model 15 KSR, then a Model 32 ASR and finally a Model 28
KSR -- with a home brew digital/electronic replacement for the paper
tape. Today it's all pixels.

 

[Benderthe.evilrobot]

<oldschool@tubes.com> wrote in message
news:52tc9c5c5kjmkfbnaiq15r5s3ig245r78j@4ax.com...

On 04 Feb 2017 23:46:23 GMT, Jim Mueller <wrongname@nospam.com> wrote:

On Sat, 04 Feb 2017 15:26:31 -0600, oldschool wrote:

On 03 Feb 2017 02:13:07 GMT, Jim Mueller <wrongname@nospam.com> wrote:

The old electrolytic capacitors you are talking about don't sound like
the oil filled variety. Indeed, if they are electrolytic, they aren't
oil filled. Oil filled capacitors aren't polarized and many of them are
good today. They were the high quality capacitors used in military and


I always thought those were oil filled, but I see I was wrong. I looked
on the web too, and it appears that most of them were filled with a
boric acid solution, which is not really harmful. They all had the tiny
vent hole in the top, and had a large threaded mounting on the bottom,
which required a sizable nut.

It's been years since I touched one of them. I only remember (vividly)
getting sprayed by one of them many years ago. It was boiling hot and it
hurt like hell. After that incident, I just replaced them before I even
pluggd in anyting that had that type of cap. (Or put a soup can over
them temporarily) They were probably the worst caps ever made.

Here is a pic I found online.
https://antiqueradio.org/art/Midwest18-3621.jpg

Progress is incremental. Those capacitors had major advantages over what
came before. The "dry" electrolytics that followed them had further
advantages. That's how things go.

I know the dry 'lytics were better, I have to ask what came before these
wet ones with the vent hole? I really dont know...

When I was a kid, I liked taking old radios to bits. A mains reservoir
electrolytic I "autopsied" had a centre electrode that was sort of like a
curvy column (for maximum surface area) up the middle, the can was the other
electrode, it was completely filled with electrolyte. Another old radio had
a compartment under the one that housed the chassis, it contained a huge
slab flat wound paper capacitor - it must've weighed at least 7lb.

 

[Benderthe.evilrobot]

"Jim Mueller" <wrongname@nospam.com> wrote in message
news:58967016$0$54323$c3e8da3$12bcf670@news.astraweb.com...

On Sat, 04 Feb 2017 04:28:09 -0600, oldschool wrote:

On Fri, 3 Feb 2017 22:05:48 -0000, "Benderthe.evilrobot"
Benderthe.evilrobot@virginmedia.com> wrote:


True. But the reason to replace them ALL is that if you only replace
the one(s) causing a problem, another will fail later, then another
still later. It is much easier to do them all at once than to have to
repair the same unit over and over as they fail one after another.
Been there, done that.

So have I.


I can totally understand what you are saying. However, I am not so sure
about whether I would want to replace all of them in certain parts of a
radio or tv. Here are my thoughts on this.

Lets take my Hallicrafters SX-99 (which I paid for but dont have yet).
That radio is 62 years old. (made in 1955). The seller said it works
fine, (and I was sent a video of it working. I did detect a very slight
hum. (But the video's audio is not the greatest).

So, as soon as I get it and play around with it, I will replace the
electrolytics in the power supply and any other 'lytics (if there are
others). Even if there is no hum, I'd replace them, just based on age.

However, this is a working radio. I ask myself if I really want to
replace all the other (small) caps. [Then I say to myself.... if it
works, dont fix it].

But, I know there are caps in specific circuits more likely to fail,
than in other circuits. Those would be caps connected to the high plate
voltages, especially at the audio output tubes and in the power supply.
I also know that if those short out, they can damage other parts, such
as tubes, resistors, and more. So, I would likely consider replacing
those. I might even consider replacing ALL the caps in the power supply,
and all audio stages, and feel safe doing that, since those caps are not
real critical as far as affecting the overall performance of the radio,
even if the new caps are a little different in their capacitance.

Where I do NOT feel comfortable changing them, are in all RF and IF
stages. The reason is that I know that a cap/coil circuit plays a big
part in the inductance, which affects the radio alignment. I am not
equipped to align the radio coils, and would prefer to leave them alone,
as long as the radio is getting good reception.

I also know that those RF and IF stages do not operate on as high
voltages as do the audio output stages. So, once again, I ask myself,
"Do I really want to risk throwing this radio out of alignment, when
it's working fine, and knowing those caps are not as likely to fail".

I answer myself "Probably not".... (As long as the radio is working
well, dont screw up a good thing.... Then too, if the caps in those
circuits are .05 or .003, I WANT a .05, not a .047. (And it seems that
.05 is no longer made).

So, if I'm satisfied with the performance of this radio, I will replace
the 'lytics regardless. I may also replace all caps AFTER the volume
control, as well as all caps in the power supply. But I will likely NOT
touch any caps in the RF and IF stages.

That's my thinking on all of this right now. Not just for this radio,
but anything..... Now, if it were simply an audio amplifier, I'd likely
replace all the caps, because audio is not all that critical.

I think that there is a misunderstanding here. The statement to replace
all the capacitors actually means all the electrolytic and paper
capacitors. Usually ceramic and mica capacitors are still good and
nobody replaces those unless they are proven to be bad.

That's not far different to what I said - certain types of cap you learn
from experience should be regarded as suspect. More reliable types can
deteriorate if they're close to the heat from power tubes. Anything that can
affect RF/IF tuning shouldn't be disturbed unless you know its faulty.

 

[Foxs Mercantile]

On 2/5/2017 9:36 AM, Nick Danger wrote:

Interesting...but I never had what I presume to be a European machine.

Started with a Model 15 KSR, then a Model 32 ASR and finally a Model 28
KSR -- with a home brew digital/electronic replacement for the paper
tape. Today it's all pixels.

Lorenz Lo-15c
<http://old.fernschreibamt-hausneindorf.de/assets/images/Arbeitsplart_Lo15c.jpg>

I started with a Teletype Model 15 in 1972, then a Model 19 in 1974.
Then got my grubby little hooks into a Model 32. I acquired the
Lorenz in 2007. It used to be in the German Consulate in Los Angeles.

For the terminal units, I started with a used homebrew with the
classic 88 mH toroids. Then graduated to the HAL ST-6000, then the
ST-8000 and currently the ST-8000A.

I'm waiting for the last of the PK-232 boxes to finally die. Because
200 Hz shift is NOT equal to 170 Hz shift. Regardless of what their
manual says.


--
Jeff-1.0
wa6fwi
http://www.foxsmercantile.com

 

[Nick Danger]

On 2/5/2017 9:36 AM, Nick Danger wrote:
Interesting...but I never had what I presume to be a European machine.

Started with a Model 15 KSR, then a Model 32 ASR and finally a Model 28
KSR -- with a home brew digital/electronic replacement for the paper
tape. Today it's all pixels.

On 2/5/2017 2:31 PM, Foxs Mercantile wrote:

Lorenz Lo-15c
http://old.fernschreibamt-hausneindorf.de/assets/images/Arbeitsplart_Lo15c.jpg

quite impressive!

I started with a Teletype Model 15 in 1972, then a Model 19 in 1974.
Then got my grubby little hooks into a Model 32. I acquired the
Lorenz in 2007. It used to be in the German Consulate in Los Angeles.

For the terminal units, I started with a used homebrew with the
classic 88 mH toroids. Then graduated to the HAL ST-6000, then the
ST-8000 and currently the ST-8000A.

Wow! Big bucks. HAL made nice equipment -- that I couldn't afford. I had
a W6FFC (Irv Hoff?) ST-6 TU kit, a 3" home brew solid state scope from
73 magazine for a tuning indicator and a W6FFC AFSK unit (for 2 meter
RTTY) all built into a Drake 4-line cabinet to match my Drake 4B line,
Heathkit scope bezel, CRT, mu metal shield and Heath knobs. Was a
avionics guy in the Air National Guard at the time and was able to use
the Airframe sheet metal shop to create the chassis and front panel.

I'm waiting for the last of the PK-232 boxes to finally die. Because
200 Hz shift is NOT equal to 170 Hz shift. Regardless of what their
manual says.

A PK-232 you say? I used a KAM+ that allowed you to very easily change
speeds (and maybe shifts) on the fly on RTTY. As a matter of fact,
that's how I worked the guy from [Russian] Georgia who was operating in
NORTH Korea on rtty. Everybody was calling him using the US 60 wpm
speed, but I was able to realize he was using the European speed (forgot
what that was), but changed it on the fly, worked him and got the North
Korea QSL to prove it.

73

 

[Ralph Mowery]

In article <o781rk$ob3$1@dont-email.me>, nick@third.eye.net says...

Wow! Big bucks. HAL made nice equipment -- that I couldn't afford. I had
a W6FFC (Irv Hoff?) ST-6 TU kit, a 3" home brew solid state scope from
73 magazine for a tuning indicator and a W6FFC AFSK unit (for 2 meter
RTTY) all built into a Drake 4-line cabinet to match my Drake 4B line,
Heathkit scope bezel, CRT, mu metal shield and Heath knobs. Was a
avionics guy in the Air National Guard at the time and was able to use
the Airframe sheet metal shop to create the chassis and front panel.

YOu started withe the kit, I could not afford that in the 1980'S.
Wired up a version of the st-6 from a schematic in Ham Radio and the
matching tone generator from the RTTY Journal on a piece of pref board
by hand. I did have a Heathkit counter to adjust the tones. Stuff
looked like crap, but worked very well.

At that time there was about 20 local hams on the 220 FM band.
I still dabble with receiving rtty on the Mod 19 from time to time.

 

[Foxs Mercantile]

On 2/5/2017 3:17 PM, Ralph Mowery wrote:
> At that time there was about 20 local hams on the 220 FM band.

Heh, I hung out on 145.85 MHz on AM AFSK.

> I still dabble with receiving rtty on the Mod 19 from time to time.

That's a pretty big chunk of "e-waste" let me know when you need to
"properly" dispose of it. ;-)



--
Jeff-1.0
wa6fwi
http://www.foxsmercantile.com

 

On Sat, 4 Feb 2017 19:54:04 -0600, Foxs Mercantile <jdangus@att.net>
wrote:

On 2/4/2017 7:25 PM, oldschool@tubes.com wrote:
Do you have any brand names to recommend for these types?
(I will be buying online, there are no electronics stores
around here).

I get mine from here:
http://www.tuberadios.com/capacitors/

Although they did not list the shipping cost, the cost of the caps is
quite reasonable, and they do have a fairly good selection.
What I am not seeing is any brand name. Who makes them?
Are they US made?

If the shipping is reasonable, I'd likely order from them based on your
referral, but it would be nice to know a little more about them.

 

On Sun, 5 Feb 2017 19:14:06 -0000, "Benderthe.evilrobot"
<Benderthe.evilrobot@virginmedia.com> wrote:

I know the dry 'lytics were better, I have to ask what came before these
wet ones with the vent hole? I really dont know...

When I was a kid, I liked taking old radios to bits. A mains reservoir
electrolytic I "autopsied" had a centre electrode that was sort of like a
curvy column (for maximum surface area) up the middle, the can was the other
electrode, it was completely filled with electrolyte. Another old radio had
a compartment under the one that housed the chassis, it contained a huge
slab flat wound paper capacitor - it must've weighed at least 7lb.

That sort of thing I never encountered. That must have been REALLY old!
Most of the stuff I worked on, was mid 40s thru 60s. I had a few of
those old wooden radios that stood about 40" tall and had a round top.
Those were some of the harder ones I tried to work on, and the tubes
were unusual. I know those were the ones that had those wet caps with
the top vent hole. I also recall that the speaker magnet was an
electro-magnet and was also used as a choke for the power supply. Those
were some of the oldest things I worked on.

 

[Jeff Liebermann]

On Sat, 04 Feb 2017 19:49:33 -0600, oldschool@tubes.com wrote:

I miss those days. The majority of newsgroups are either dead or filled
with morons or off topic political based fighting and name calling these
days. There were many worthwhile newsgroups that I used to enjoy, and I
wont even go there anymore.

The surest sign of success is abuse and pollution. Usenet is
obviously successful.

I wrote this rant on Usenet "personalities" maybe 20 years ago when
observed the same problems you've mentioned:
<http://802.11junk.com/jeffl/crud/genesis.txt>

>I cant understand where everyone went.

Probably Reddit:
<https://www.reddit.com/r/VintageRadios/>
<https://www.reddit.com/r/vintageaudio/>
<https://www.reddit.com/r/audiorepair/>

I know almost everyon has an
account with that miserable facebook these days (except me), but I cant
say I have ever seen any useful discussions on FB.

I have a Facebook account and I'm not afraid to use it. Mostly, I
hang round two local groups that deal with the usual neighborhood
problems. It works fairly well, and much better than the old bulletin
board outside the post office or market. It might work better if I
take the time to learn how to navigate the Facebook maze.

My only affordable internet access is still
dialup, because that's all there is in this rural area where I live, and
bloated websites like FB and most of the news media sites wont even load
anymore).

Check into alternatives to cable and telco internet. There are plenty
of WISP's (wireless internet service providers).
<http://www.wispa.org/Directories/Find-a-WISP>
Maybe share a wireless backhaul connection with the neighbors. I
setup a few such systems using various backhauls (including
satellite). They were slow and clumsy, but sufficient as the
alternative would have been dialup or no internet.

Also, you can really cut down on the traffic by using the mobile URL's
instead of the usual URL. Try it:
<https://m.facebook.com>
<https://m.google.com>
etc... You may need to install a browser addon that fakes the user
agent string, so that the web pile thinks you're using a smartphone.
<http://www.howtogeek.com/113439/how-to-change-your-browsers-user-agent-without-installing-any-extensions/>
For example:
<https://addons.mozilla.org/en-US/firefox/addon/user-agent-switcher/>
There are others. There are also browser tweaks for dialup:
<http://lifehacker.com/140120/geek-to-live--how-to-survive-a-slow-internet-connection>
Or, you can switch to a text based browser.
<https://en.wikipedia.org/wiki/Text-based_web_browser>
However, I'm not sure it will work with Facebook.


--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

 

On Sun, 05 Feb 2017 13:58:00 -0800, Jeff Liebermann <jeffl@cruzio.com>
wrote:

On Sat, 04 Feb 2017 19:49:33 -0600, oldschool@tubes.com wrote:

I miss those days. The majority of newsgroups are either dead or filled
with morons or off topic political based fighting and name calling these
days. There were many worthwhile newsgroups that I used to enjoy, and I
wont even go there anymore.

The surest sign of success is abuse and pollution. Usenet is
obviously successful.

I wrote this rant on Usenet "personalities" maybe 20 years ago when
observed the same problems you've mentioned:
http://802.11junk.com/jeffl/crud/genesis.txt

I cant understand where everyone went.

Probably Reddit:
https://www.reddit.com/r/VintageRadios/
https://www.reddit.com/r/vintageaudio/
https://www.reddit.com/r/audiorepair/

I'll have to look at those. I personally hate web based forums, but that
is mostly bcause on dialup, it takes too long to load the pages. I used
to go ro some of those Yahoo Groups, years ago, but even them have been
taken over by spam trolls and abuse.

I know almost everyon has an
account with that miserable facebook these days (except me), but I cant
say I have ever seen any useful discussions on FB.

I have a Facebook account and I'm not afraid to use it. Mostly, I
hang round two local groups that deal with the usual neighborhood
problems. It works fairly well, and much better than the old bulletin
board outside the post office or market. It might work better if I
take the time to learn how to navigate the Facebook maze.

Some people seem to like FB. I actually had an account for a very short
time. After spending many hours trying to understand how to use it, (and
it's not easy), I made a page for a small non-profit event that I run.
It took less than one week for idiots to ruin it. Nothing posted to it
had anything to do with the topic. It became a place for people to beg
for money, call other people names, discuss politics, and post photos of
themselves drunk. Since I could only work on it from the library or a
local restaurant (using the WIFI), I finally turned the page over to
another member of our group and said here is the group and the password,
FIX THIS. After a week or so, they said that I had not made it limited
enough, and it was beyond fixing. I told them to remove everyone from
the "friends list" except the actual members of our organization.
But even doing that did not seem to stop the abuse of the site (page).
Out of extreme frustration, I deleted the whole thing, and said I would
never touch FB again.

My only affordable internet access is still
dialup, because that's all there is in this rural area where I live, and
bloated websites like FB and most of the news media sites wont even load
anymore).

Check into alternatives to cable and telco internet. There are plenty
of WISP's (wireless internet service providers).
http://www.wispa.org/Directories/Find-a-WISP
Maybe share a wireless backhaul connection with the neighbors. I
setup a few such systems using various backhauls (including
satellite). They were slow and clumsy, but sufficient as the
alternative would have been dialup or no internet.

Also, you can really cut down on the traffic by using the mobile URL's
instead of the usual URL. Try it:
https://m.facebook.com
https://m.google.com
etc... You may need to install a browser addon that fakes the user
agent string, so that the web pile thinks you're using a smartphone.
http://www.howtogeek.com/113439/how-to-change-your-browsers-user-agent-without-installing-any-extensions/
For example:
https://addons.mozilla.org/en-US/firefox/addon/user-agent-switcher/
There are others. There are also browser tweaks for dialup:
http://lifehacker.com/140120/geek-to-live--how-to-survive-a-slow-internet-connection
Or, you can switch to a text based browser.
https://en.wikipedia.org/wiki/Text-based_web_browser
However, I'm not sure it will work with Facebook.

I am a lot more limited than you could imagine. My nearest neighbor is
over a mile away. The nearest small town is 5 miles, the nearest large
city is 55 miles. I can not get a reliable cell phone signal here. To
make a call, I have to either drive up the hill, or (in warm weather), I
may go up on the roof. Because of that, I MUST keep a landline (which
also takes care of my dialup needs). There is no cable. The only way
might be a satellite dish. And that would cost me at least $100 per
month. I dont want the tv part of it. I dont watch much tv and I only
watch ME-TV (oldies). My antenna on the 35 foot tower I made from pipe,
works pretty well for tv, but only gets stations from one direction,
since there's a hill on my other side.

I am going to check on some of these text based browsers and stuff like
that though. At one time, I used a browser called "Off By One", which
only displayed text and pics. But it will not work on any websites using
HTTPS (secured), and many of them are using that now, even wikipedia.

Thanks

 

[Jim Mueller]

On Sat, 04 Feb 2017 19:25:31 -0600, oldschool wrote:

On 05 Feb 2017 00:21:42 GMT, Jim Mueller <wrongname@nospam.com> wrote:

I think that there is a misunderstanding here. The statement to replace
all the capacitors actually means all the electrolytic and paper
capacitors. Usually ceramic and mica capacitors are still good and
nobody replaces those unless they are proven to be bad.

The paper capacitors in the IF and RF stages need to be replaced even if
the radio "works". Leaky capacitors change the voltages on the tubes
causing them to work at less than their best performance. Also, these
capacitors are used as supply bypasses and AVC filter capacitors. They
do not affect the alignment of the set; the ceramic and mica capacitors
may. Their value is not particularly critical; pick the closest modern
value.

I hear you.....

Consider the value issue. If the radio has a .05 uF, 20% capacitor in
it, its actual value can be anywhere from 0.04 uF to 0.06 uF. A modern
0.047 uF 10% capacitor can be between .0423 uF and 0.0517 uF. So the
0.047 uF capacitor can be closer to 0.05 uF than the old one marked with
that value.

OK. That makes sense...

As for life expectancy, there was a time in the late '50s and early '60s
when both paper and plastic film capacitors were used. The paper
capacitors I have from that period are universally bad while the plastic
film ones are almost always good. Plastic film has passed the test of
time.

As for what type of plastic film to use, polyester (AKA Mylar) is the
cheapest and has the poorest performance. But it is still better than
the paper capacitors of old so it is suitable for use just about
anywhere a paper capacitor was formerly used. Polycarbonate (no longer
made) and polypropylene are better but more expensive. Polystyrene
capacitors are also very good and inexpensive but are usually seen only
in small values

I see where this can get confusing. I'll consider the polyester (AKA
Mylar), but for the small cost difference, I'd probably prefer the best.
It looks like polypropylene would be that choice.

Do you have any brand names to recommend for these types?
(I will be buying online, there are no electronics stores around here).

and are frequently not seen at all. They also have the problem that
they melt at lower temperatures than other plastic capacitors and
solvents dissolve them. Still, within their limitations, they are
excellent.


Dont you mean they melt at a *HIGHER* temperature? I cant imagine how
something could melt at a low temp?

Upon reading a URL that somone posted on here, I see where the
audiophliles say that some caps have better sound quality, than others.
On a SW radio, I'm not really looking for "precision sound", but more so
for best performance from the signal coming from the antenna to the
speaker. And while some (or most) of these newer types of caps are made
to be used with modern gear, containing semiconductors, which are the
best choice for old tube stuff. I would think that the caps should mimic
the old paper caps, because that is what these circuits were designed to
use. I know the values of caps are the capcitance (in MF or MMF) and the
voltage. But I know there are other factors that I know nothing about.
Someone mentioned tempco (is that what I read?) in another message in
this thread. What the heck is that?

Either way, I do believe the caps should be similar to the original ones
to work properly. Just made from better materials.


--
Jim Mueller wrongname@nospam.com

No, polystyrene capacitors have LOWER maximum temperature capability than
most other capacitors; that is one of their limitations. But they have
very low leakage, last forever if not mistreated, and are cheap.

Tempco is shorthand for temperature coefficient. It describes how much
the capacitance changes as temperature changes. Some capacitors change
very little (for example C0G ceramics), others change a LOT (Z5U
ceramics).




--
Jim Mueller wrongname@nospam.com

To get my real email address, replace wrongname with dadoheadman.
Then replace nospam with fastmail. Lastly, replace com with us.