Does anyone know what the specs are for the wide and narrow filters,
i.e. the bandwidth and shape factors? I love this radio but the narrow
filter doesn't seem to make very much of a difference to my ears, as
far as interference rejection goes. Has anyone ever replaced either
filter with good results, and what filter did you use? Thanks!

In article .com,
wrote:

Does anyone know what the specs are for the wide and narrow filters,
i.e. the bandwidth and shape factors? I love this radio but the narrow
filter doesn't seem to make very much of a difference to my ears, as
far as interference rejection goes. Has anyone ever replaced either
filter with good results, and what filter did you use? Thanks!

Is there a page that lists some of the Pana models??

I saw one on the flea market, that had an AM antenna
that could be turned, a signal meter, I guess narrow wide too...

Marc

--

willismat wrote:

Does anyone know what the specs are for the wide and narrow filters,
i.e. the bandwidth and shape factors? I love this radio but the narrow
filter doesn't seem to make very much of a difference to my ears, as
far as interference rejection goes. Has anyone ever replaced either
filter with good results, and what filter did you use? Thanks!

---------------------------------
I once checked the filters, but it was back in the early
1980s. I can remember they were both rather wide.
I thought about trying to replace them, but the tunning
wasn't fine enough and the receiver wasn't stable
enough for the effort.
It had great sound on FM and good sound quality,
in spite of the over wide fitlers, on AM an SW. I loaned
mine to a friend and it was destroyed along with her
car.
One simple mod you might want to consider is to add
a 7806 linear regulator, with a switch hidden in the
battery compartment in the little space intended for
the earphone. It was a fun radio to take on picnics
and camping. I have often thought of buying another
one, but I have "too" many radios. Or at least not
enough space to stash many more.

I think the RF200 had a "stnadard" 455KHz IF, and if
so, then scalvaged CB IF filters ought to work. The
RF2200 is not at all crowded inside. Good luck on
your quest. A good"cheap" source of narrow filters
can be the lowly CB. I picked up several at the local
thrift stores for next to nothing when they are missing
the mics. I even got a couple of SSB units that had
nice, narrow ceramic filters.
Next to nothing means less then 5$.

Garage sales are another good source. It helps if your
wife has friends who think garage sales are a Holy
mandate. I have a set deal, buy me all the CBs you find
for $5 or less. I help with their home PCs os it balances
out.

Terry

I've used several of the Panasonic RF-2xxx series. My impression was
that the filter positions were best described as wide and wider with
outward curving skirts. They were useful in AM mode but were too wide
for ssb in the crowded ham bands. A good announcer on a shortwave
station in the clear sounds great in the wide position and pretty
darned good in narrow.

The downside to installing a narrow communications filter is that you
could compromise sound quality on AM broadcasts.

If it were me I would enjoy the 2200 for what it is and find a good
tabletop with better filters and the requisite stability to handle ssb.

the RF-2200 does not have "real" ceramic filters. like the 2800, there are
just some tuned circuits for selectivity in the wide mode and in the narrow
mode a "transfilter" is switched in.
therefore selectivity is quite cheesy.

to combat this, I am in the process of creating a SUPER RF-2800 !!!!!
I have added an LF-D6 filter in the wide position and will be adding a coax
antenna input for my portable ramsey AA7 custom antenna. I am looking into
other things so soup up. I will report on this as it progresses.


the RF-2200 can be significantly improved with quality ceramic filters.

Radio West in the early 80's used to offer a collins mechanical filter
upgrade for the 2800/2900. My FRG-7700 has two of these upgrade filters, 1.9
and 2.9





wrote in message
oups.com...
Does anyone know what the specs are for the wide and narrow filters,
i.e. the bandwidth and shape factors? I love this radio but the narrow
filter doesn't seem to make very much of a difference to my ears, as
far as interference rejection goes. Has anyone ever replaced either
filter with good results, and what filter did you use? Thanks!

Leonard Martin wrote:

A good"cheap" source of narrow filters
can be the lowly CB. I picked up several at the local
thrift stores for next to nothing when they are missing
the mics. I even got a couple of SSB units that had
nice, narrow ceramic filters.
Next to nothing means less then 5$.

Terry

What do you do with all those CBs?

Leonard
Leonard Martin Jun 22, 10:38 pm show options
Newsgroups: rec.radio.shortwave
From: Leonard Martin - Find messages by
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Date: Wed, 22 Jun 2005 21:38:39 -0500
Local: Wed,Jun 22 2005 10:38 pm
Subject: Panasonic RF-2200
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In article .com,

- Hide quoted text -
- Show quoted text -
wrote:
willismat wrote:

Does anyone know what the specs are for the wide and narrow filters,
i.e. the bandwidth and shape factors? I love this radio but the narrow
filter doesn't seem to make very much of a difference to my ears, as
far as interference rejection goes. Has anyone ever replaced either
filter with good results, and what filter did you use? Thanks!

---------------------------------
I once checked the filters, but it was back in the early
1980s. I can remember they were both rather wide.
I thought about trying to replace them, but the tunning
wasn't fine enough and the receiver wasn't stable
enough for the effort.
It had great sound on FM and good sound quality,
in spite of the over wide fitlers, on AM an SW. I loaned
mine to a friend and it was destroyed along with her
car.
One simple mod you might want to consider is to add
a 7806 linear regulator, with a switch hidden in the
battery compartment in the little space intended for
the earphone. It was a fun radio to take on picnics
and camping. I have often thought of buying another
one, but I have "too" many radios. Or at least not
enough space to stash many more.

I think the RF200 had a "stnadard" 455KHz IF, and if
so, then scalvaged CB IF filters ought to work. The
RF2200 is not at all crowded inside. Good luck on
your quest. A good"cheap" source of narrow filters
can be the lowly CB. I picked up several at the local
thrift stores for next to nothing when they are missing
the mics. I even got a couple of SSB units that had
nice, narrow ceramic filters.
Next to nothing means less then 5$.

Garage sales are another good source. It helps if your
wife has friends who think garage sales are a Holy
mandate. I have a set deal, buy me all the CBs you find
for $5 or less. I help with their home PCs os it balances
out.

Terry

What do you do with all those CBs?

Leonard

--
"Everything that rises must converge"
--Flannery O'Connor
-------------------------------------
I have been hunting for better Murata ceramic
IF fitlers. I have several radios to upgrade.

I have converted several to "outboard" IF strips.
Buffer the 455 KHz in a SW, feed it to the modified
CB and instant better, as in more slective receiver.
And some of the better ones I fix and give/trade to
friends. The SSB ones are worth converting to 10
mtrs. Several of us have an very informal net on
10mtrs.

I like to experiment. I have a very nice sears(Uniden)
SSB that I plan on convering to 17Mtrs. I always have
more interests then time.

Murata no longer sells the really nice fitlers, so unless
one has a vender with some stashed, this is the only
way to get them. I generally get a CB a month. CBs are
full of usefull RF parts. RF Power transistors, RF chokes
etc.

But the best ceramic filters pales when compared to a even a
poor crystal filter. And good crystal filters must be heard to be
aprreciated. You can stack up to 3 simialr ceramic fitlers for
improved skirts. But crystal filters are better. And expensive.

When I get the chance I am going to replace the stock filters in
our(my wife and I each have one)DX398s.

Terry
-----------------------------------------------------

) writes:
Leonard Martin wrote:

A good"cheap" source of narrow filters
can be the lowly CB. I picked up several at the local
thrift stores for next to nothing when they are missing
the mics. I even got a couple of SSB units that had
nice, narrow ceramic filters.
Next to nothing means less then 5$.

Terry

What do you do with all those CBs?

He just said, he uses them as a source of cheap but narrower filters.

Michael

Thanks to all who replied. The only information I could find on filter
specs, which I'm really curious about now, is from DXing.com's website
regarding two other Panasonic portables of the time. The specs for
those a

RF-2600 6 and 4 kHz
RF-2800 5 and 3.4 kHz

I've never used either of these two radios, but I have to think that
the 2200 is more likely to be the same as the 2600 as far as bandwidth
goes. The wide is fine for general program listening when there's
little interference, but when it's needed the narrow doesn't usually
come to the rescue. If the 2200 does use tuned circuits then it would
be best to accept it as it is and be happy with what it does do well,
and get a desktop for the tougher signals.

actually, the 2800 was of the same era as the 2200. the 2600 came out years
later, being a cheaper version of the 2900.

definitely, a properly selected desktop or modified laptop would be a better
choice.

remember, just because something is a desktop doesn't make it better. there
have been quite a few desktops over the past few years that need significant
help with selectivity ! the Drake R8 and SW8 series are some of the few that
don't need any help.
even some of the $1000 receivers required optional filters to work well. the
R5000 being the most notable.



wrote in message
ups.com...
Thanks to all who replied. The only information I could find on filter
specs, which I'm really curious about now, is from DXing.com's website
regarding two other Panasonic portables of the time. The specs for
those a

RF-2600 6 and 4 kHz
RF-2800 5 and 3.4 kHz

I've never used either of these two radios, but I have to think that
the 2200 is more likely to be the same as the 2600 as far as bandwidth
goes. The wide is fine for general program listening when there's
little interference, but when it's needed the narrow doesn't usually
come to the rescue. If the 2200 does use tuned circuits then it would
be best to accept it as it is and be happy with what it does do well,
and get a desktop for the tougher signals.