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Valve Radio Vs Solid State Radio

S

Steve Batt

Jan 1, 1970
0
Patrick Turner said:
The manuals on line for the Tivoli Audio AM/FM radios don't include the AF
response data.

So I will assume the products are junk.

Ain't it grand the way idiots advertise their products,
but they don't tell you what you could expect.

Patrick Turner.


Remember Patrick that assume made an ass out of u and me.

I have one of these table radios and they certainly do not sound 'junk',
have a listen before you pass comment.

Steve
 
P

Patrick Turner

Jan 1, 1970
0
Remember Patrick that assume made an ass out of u and me.

I have one of these table radios and they certainly do not sound 'junk',
have a listen before you pass comment.

To escape from what I am left to assume, what is the
measured AF bw for the AM radio?

Patrick Turner.
 
S

Steve Batt

Jan 1, 1970
0
Patrick Turner said:
To escape from what I am left to assume, what is the
measured AF bw for the AM radio?

Patrick Turner.
You know, I cannot answer that question
I am at least going on what my ears tell me not what is not told to me by
the manufacturers. As I said above 'have a listen'
 
P

Patrick Turner

Jan 1, 1970
0
Steve said:
You know, I cannot answer that question
I am at least going on what my ears tell me not what is not told to me by
the manufacturers. As I said above 'have a listen'

One day I might.

Too busy right now to farnarkle around with AM radios.

Patrick Turner.
 
J

Joerg

Jan 1, 1970
0
Hello Patrick,
Not a chance, without being intrusive and un-neighbourly.

In our neighborhood we'd walk over there with a six pack of Fosters. Or
a bottle of Merlot. Then you are always welcome ;-)
I placed a few ferrites around the mains input active and neutral,
and it made no difference.
I don't like placing a cap across my mains.

Did you place ferrites separately on each wire? Common mode filtering
doesn't always work. I had to do that on a (new!) printer. Ten turns or
so each on large #43 toroids, one per line. That did the trick.

However, if the stuff gets re-radiated from your neighbor's house wiring
there is nothing you can do (except for the method above...).

Regards, Joerg
 
P

Patrick Turner

Jan 1, 1970
0
Joerg said:
Hello Patrick,


In our neighborhood we'd walk over there with a six pack of Fosters. Or
a bottle of Merlot. Then you are always welcome ;-)


Did you place ferrites separately on each wire? Common mode filtering
doesn't always work. I had to do that on a (new!) printer. Ten turns or
so each on large #43 toroids, one per line. That did the trick.

I am talking about the mains wires from the power pole.
There is no way I could wind both active and neutral
around ferrite torroids ten times.

I just clamped ferrites onto the wires.
It made zero difference.

However, if the stuff gets re-radiated from your neighbor's house wiring
there is nothing you can do (except for the method above...).

And I don't have a shooter's licence.
I forgot the poison recipe I had.....

But the hum is far worse with a long wire antenna compared to a ferrite rod,

so methinks the hum is due to electrostatic pick up rather than magnetic
pick up.

Patrick Turner.
 
J

Joerg

Jan 1, 1970
0
Hello Patrick,
But the hum is far worse with a long wire antenna compared to a ferrite rod,

so methinks the hum is due to electrostatic pick up rather than magnetic
pick up.

Methinks the same. Then it will probably also be difficult to notch it
out by rotating the ferrite rod.

Regards, Joerg
 
P

Patrick Turner

Jan 1, 1970
0
Joerg said:
Hello Patrick,


Methinks the same. Then it will probably also be difficult to notch it
out by rotating the ferrite rod.

Regards, Joerg

Along with my own kitchen set which I built, I had
3 customers radios going today.
The '56 Grundig hums a bit, an Oz '48 Kriesler hardly hums at all,
a '60 Astor ditto, and mine hums a lot.
Only the Astor has a ferrite rod.
Placing any king of caps across the mains inputs, or from A&N to chassis
makes no difference.
placing 0.01 caps across diodes made zero difference; the noise when tuned to
846 kHz stayed put.

The Grundig improved a lot when its chassis was earthed, like my own design did.

A long wire antenna taken up over the roof was worse.

I can only conclude that where I am, which is only 5Km away from a
5,000 ABC watt AM transmitter, I still have appalling interference on many
sets.

My next step is to try a shielded loop antenna, with the coil inside an aluminium
case
which is carefully prevented from being a shorted turn.

Patrick Turner.
 
J

Joerg

Jan 1, 1970
0
Hello Patrick,
My next step is to try a shielded loop antenna, with the coil inside an aluminium
case
which is carefully prevented from being a shorted turn.

That would make a nice antenna and I'll do the same some day. Most
people use copper pipe for it because it is solderable and very
available in hardware stores. When you polish and then lacquer coat it
the antenna would also have a cool look.

If grounding did make a difference maybe you could try a huge common
mode choke. One that loops all three (hot, neutral, PE) through a large
ferrite. Maybe a big #77 core or the pot core from a surplus PC power
supply. If you fuse it at a few amps before the choke you may be able to
use thinner lines and avhieve more turns.

Regards, Joerg
 
P

Patrick Turner

Jan 1, 1970
0
Joerg said:
Hello Patrick,


That would make a nice antenna and I'll do the same some day. Most
people use copper pipe for it because it is solderable and very
available in hardware stores. When you polish and then lacquer coat it
the antenna would also have a cool look.

AL channels are easier, and can be fitted over a wooden coil
former.

If grounding did make a difference maybe you could try a huge common
mode choke. One that loops all three (hot, neutral, PE) through a large
ferrite. Maybe a big #77 core or the pot core from a surplus PC power
supply. If you fuse it at a few amps before the choke you may be able to
use thinner lines and avhieve more turns.

I think the problem is with a long wire antenna picking up the signal with hum
modulation.
I have not tried a toroid with well insulated turns wound trifilar.

Presumably that make a high Z series impedance to all 3 wires from the power point.
Then Ideally I should have to earth the set to an earth stake away from the
water pipes, probably also riddled with
hum modulated signals.

Its a lot of bother to have to go to.

Patrick Turner.
 
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