Date   

Re: Favorite digital under 400. ?

John M. Tooley <jmtooley@...>
 

ReVox B 760

----- Original Message -----
From: jimrivers3
Sent: Saturday, April 06, 2002 11:14 PM
Subject: [FMtuners] Re: Favorite digital under 400. ?

The Carver TX-11 for looks only. Or the Amber model 7.  Both a
pleasant change from the button infested, sameness of most digital
black boxes.
--- In FMtuners@y..., "newaag" <newaag@y...> wrote:
> I'm soliciting inputs for your favorite digital tuner under 400.
> Favorite can mean whatever is important to you - Sound quality, DX
> capability, looks (for Jim), or sophistication of design on paper
> (for David Rich fans).
>
> This will go over to the POLL section once anyone bothers to
respond.
> For starters:
>
> Onkyo TX-9090/II
> Yamaha TX-85
> Yamaha TX-950
> Tamaha TX-1000
> Carver TX-11
> HK Citation 23
> Sansui TU-S9
> Denon TU-850
> ???
>
> Bob



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Re: Favorite digital under 400. ?

newaag
 

Hi Gary
Thanks for bringing this one to our attention.
When you have a minute, I'd love to know what stereo decoder chip is
used in that one (LA3401, LA3450, etc)
Also, if there is a description of the detector circuit with any
details (PLL, balanced output, etc)

I am finding it interesting to listen to the tuners that have what is
considered by David Rich (and others)to be the best MPX chip ever put
into a home audio tuner, the Sanyo LA3450. It is the one that
uses "Walsh functions", and so far seems to have been used by Sansui,
Yamaha (TX900U, TX950), Harman Kardon (TU-9600), and I'm sure many
others. The LA3450 MPX decoder seems to have become available in the
mid to late 80's, and is still in production, although I'm not aware
of any current production units that use it. Suprisingly, the
Accuphase T-109 uses the LA-3401, but benefits from replacement with
the LA3450 (not an easy job we are told).

Bob

--- In FMtuners@y..., "gbronn" <gbronn@y...> wrote:
Bob,
Have you ever listened to a JVC FX-1100? Don Scott reviewed it in
Stereophile in the late 80's when it was new and raved about it,
saying it was one of the new wave of digital tuners that were
capable of competing with the likes of the MR78, Kenwood 600T, and
Sansui TX-1. Probably a bit of hyperbole there, but it is a good
tuner.
They listed for $470 in the late 80's. I picked up a demo unit
from
the Wiz for almost no money in the early 90's and its been doing a
great job for me since. It seems to pick up all the stations that
I
can get with the MR78 and sounds pretty good now that I've tweaked
the audio section.
It does have the very annoying feature that the mute control is
tied
to the stereo/mono switch.
I've never seen one of these for sale on ebay, so I suspect that
not
many were sold, but its worth checking out if you stumble across
one.
---Gary
--- In FMtuners@y..., "newaag" <newaag@y...> wrote:
I'm soliciting inputs for your favorite digital tuner under 400.
Favorite can mean whatever is important to you - Sound quality,
DX
capability, looks (for Jim), or sophistication of design on paper
(for David Rich fans).

This will go over to the POLL section once anyone bothers to
respond.
For starters:

Onkyo TX-9090/II
Yamaha TX-85
Yamaha TX-950
Tamaha TX-1000
Carver TX-11
HK Citation 23
Sansui TU-S9
Denon TU-850
???

Bob


Re: Favorite digital under 400. ?

gbronn
 

Bob,
Have you ever listened to a JVC FX-1100? Don Scott reviewed it in
Stereophile in the late 80's when it was new and raved about it,
saying it was one of the new wave of digital tuners that were
capable of competing with the likes of the MR78, Kenwood 600T, and
Sansui TX-1. Probably a bit of hyperbole there, but it is a good
tuner.
They listed for $470 in the late 80's. I picked up a demo unit from
the Wiz for almost no money in the early 90's and its been doing a
great job for me since. It seems to pick up all the stations that I
can get with the MR78 and sounds pretty good now that I've tweaked
the audio section.
It does have the very annoying feature that the mute control is tied
to the stereo/mono switch.
I've never seen one of these for sale on ebay, so I suspect that not
many were sold, but its worth checking out if you stumble across one.
---Gary
--- In FMtuners@y..., "newaag" <newaag@y...> wrote:
I'm soliciting inputs for your favorite digital tuner under 400.
Favorite can mean whatever is important to you - Sound quality, DX
capability, looks (for Jim), or sophistication of design on paper
(for David Rich fans).

This will go over to the POLL section once anyone bothers to
respond.
For starters:

Onkyo TX-9090/II
Yamaha TX-85
Yamaha TX-950
Tamaha TX-1000
Carver TX-11
HK Citation 23
Sansui TU-S9
Denon TU-850
???

Bob


Re: Marantz 10b Selectivity

aa6zd <k6kc@...>
 

--- In FMtuners@y..., mjzuccaro@a... wrote:
In a message dated 3/12/02 5:50:27 PM Pacific Standard Time,
k6kc@l... writes:

<< 000th tuner being in sight",
if I recall the phrase correctly. My 10B's serial number is circa
5300, and the R.F. 'deck' has the Marantz location as "Woodside",
rather than "Long Island City". It is the only 10B I've ever seen
that
didn't state "Long Island City."
I haven't had the bottom plate off in a long time, but I recall
that
it has a small P.C. board, containing one DIP integrated circuit,
and
a handfull of passive parts. The installatio >>
Lowell:
The Woodside factory was indeed in Long Island City. I've got
photos of both
Marantz facilities, the later one was a custom built building with
roof
parking that still stands .

Your unit must have been modified, I'll wager someone put in a PLL
mpx chip.
That tuner, though built thru about '69 or '70, was unchanged since
it's
introduction around '64. Never any I.C's used in factory production.
Best,
Mike Z.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Thanks for the info., Mike.
Sorry about being so slow.
Your theory about the PLL conversion is certainly a possibility.
I'll have to tear into it and see just what is going on with the
circuit board.
So, does anyone else have any data on the last 10B to 'roll off the
line'? Mine has a Q.C. sticker on the rear chassis apron that
reminds me of the ones that were applied to the solid state Marantz
gear that was built in Sun Valley, Ca., after Superscope purchased
them. Like the "Woodside" labeling, I've never seen another 10B with
this sticker.
Thanks,
Lowell
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++


Re: Favorite digital under 400. ?

jimrivers3 <jimrivers3@...>
 

The Carver TX-11 for looks only. Or the Amber model 7. Both a
pleasant change from the button infested, sameness of most digital
black boxes.
--- In FMtuners@y..., "newaag" <newaag@y...> wrote:
I'm soliciting inputs for your favorite digital tuner under 400.
Favorite can mean whatever is important to you - Sound quality, DX
capability, looks (for Jim), or sophistication of design on paper
(for David Rich fans).

This will go over to the POLL section once anyone bothers to
respond.
For starters:

Onkyo TX-9090/II
Yamaha TX-85
Yamaha TX-950
Tamaha TX-1000
Carver TX-11
HK Citation 23
Sansui TU-S9
Denon TU-850
???

Bob


Re: Realistic TM-1001

scottallwave <scottallwave@...>
 

I hate to mention such a lowly brand name in such exalted company,
but I acquired a Realistic TM-1001 tuner and it sounds surprisingly
good. Does anybody else have any experience with this device? It
sounds a bit sweeter (tube-like) than my Kenwood KT-7001. I haven't
compared it to the Magnum Dynalab FT-101A yet.
Chris Campbell

Hi Chris,
Your unit was built by Pioneer. I've owned the TM1001 and TM1000.
Still have the 1000, it's a nice unit for a bedroom system or if the
main unit is down. It does sound good. Still haven't pulled my 101A
out of the closet for the last few years as it sounds thinner to me.
I should try it again. A nice sounding unit from the 101A "era" is the
Creek CAS3040 from Britain.


Favorite digital under 400. ?

newaag
 

I'm soliciting inputs for your favorite digital tuner under 400.
Favorite can mean whatever is important to you - Sound quality, DX
capability, looks (for Jim), or sophistication of design on paper
(for David Rich fans).

This will go over to the POLL section once anyone bothers to respond.
For starters:

Onkyo TX-9090/II
Yamaha TX-85
Yamaha TX-950
Tamaha TX-1000
Carver TX-11
HK Citation 23
Sansui TU-S9
Denon TU-850
???

Bob


Re: Latest on IBOC digital FM

newaag
 

Mike -
Interesting news.
I still think the automotive OEM market will decide the fate of IBOC.
So far, it seems they (carmakers) will be more interested in other
cool things, like GPS driven real time maps and voice activated
email. Although IBOC is *new*, it basicly serves up the same thing in
a new delivery format. As most people listening in cars currently
don't have complaints about the quality of FM stations, it solves a
problem that, customer perception wise, does not exist. And if the
range of IBOC is worse, rather than better (as I understand it is)
you now have no perceived positives, and a big negative. Should be
fun to watch. As far as I can tell, HDTV is far far ahead of IBOC,
and it is slated for 2006 across the board turn on.
Bob
--- In FMtuners@y..., mjzuccaro@a... wrote:
Guys:
From this weeks "Radio World":

Ibiquity Digital Corp will be rolling it out at the 2002 NAB
convention. 3
transmitter manufacturers- Harris, Broadcast Electronics, and
Nautel, will be
showing IBOC transmitters. Infinity Broadcasting has tested it so
far in 5
cities on 5 stations.

Cost of changeover for xmtr facilities to be between $27k-250k per
station.

We'll see what happens.

Best,
mike Z.


Re: Marantz 10B IF Filter Module Frequency Response?

bta_50g <jbyrns@...>
 

--- In FMtuners@y..., mjzuccaro@a... wrote:
John:
1- Yes, identical
2- Some time ago I swept one- about 350 kc wide, not perfectly flat. Dont
forget that there are 6 in series, the bandwith reduction factor gets it down
to about 225kc.
Hi Mike,

Thanks for the input. At what point is the 350 kHz measured, -3 dB, -
6 dB, or ?

Do you know what the peak separation on the discriminator is?


John


Re: More on KT-8300 op amp upgrades--Fixed Mine!

newaag
 

Ryan;
Great to hear this worked! I'll remember to scope this and takes
pictures when I do my KT-8300. DIY amp builders will be familiar with
the selection of these caps bypassing the feedback resistor (those
building amps with feedback). The quick adjustment procedure for amps
is this: play a square into the amp, with a load that included some
capacitance, then monitor the output with a scope. You play with cap
values until you can eliminate the ringing on the square wave. With
too small a cap, (or no cap) it can break into oscillation, worst
case, or show ringing on the square wave. Too large a cap will roll
off the high end.
I guess the old op-amps in the KT-8300 had such limited bandwith that
it was not neccessary.

--- In FMtuners@y..., "the_indominatable_rhyno" <rzcolem@s...> wrote:
just tried this on my KT8300. fixed the high speed whirring that
was
active whenever there was a stereo signal (this problem was a
result
of upgrading IC 11 & 13 to BB2604 opamps).


Re: More on KT-8300 op amp upgrades--Fixed Mine!

the_indominatable_rhyno <rzcolem@...>
 

just tried this on my KT8300. fixed the high speed whirring that was
active whenever there was a stereo signal (this problem was a result
of upgrading IC 11 & 13 to BB2604 opamps).

oh btw, check AC to ground...found that my KT8300 have VAC of 97.9 in
+, but 34 when -. you can fix this easy by taking off the bottom
panel and swapping where the two power cord leads attach...

listening impressions will be coming in the next few days...seems to
be singing far beyond the $130 i have invested...

best
ryan

--- In FMtuners@y..., mjzuccaro@a... wrote:
In a message dated 4/4/02 10:14:48 PM Pacific Standard Time,
newaag@y...
writes:

<< 20kohm. You want to try soldering
a 10 to 100 pF cap directly across the leads of these 4 feedback
resistors listed above. For experimenting, use any cap available,
even ceramic. If this improves the sound, you have eliminated a
high
frequency problem, most likely oscill >>
And very short leads- at 100mc even small caps can be resonant.
Bad news.
Use the smallest micas you can find.
MZ


Any experience/info re: Harman/Kardon Citation 18 tuner?

blundry <blundry@...>
 

Hello group:

I'm not an FM tuner expert by any means, but have been following many
of the threads here on FMtuners for several months, particularly to
learn more about the performance of analogue tuners of the 1975 to
1982 vintage. I am more interested in an audiophile tuner than in the
ultimate DX machine, but believe that a well executed design should
satisfy both groups of tuner enthusiasts.

On a bit of a lark I bought a Harman/Kardon Citation 18 tuner on eBay
for only $20. It was untested, and I figured if it were working, it
would a terrific bargain. I've always been a Harman/Kardon fan, and
have an H/K tapedeck and VCR in my system. At the time, I didn't know
much about this particular tuner, which is a solid state design that
dates from about 1977 or so and apparently retailed for $595. The
Citation products were H/K's flagship designs, often incorporating new
ideas and technologies, though I'm not clear how the Citation 18
differs from earlier H/K tuners. It is card based, much like a modern
PC, with a different plug-in board for the power supply,
monitor(headphone)amplifier(two of them!), meter/mute, MPX, output
amplifier, and FM/IF. Other than ease of repair, I'm not sure of any
advantage to this type of set-up, unless the idea was that different
boards would upgradeable at a later date. That idea would have been
pretty progressive in 1977, but I'm not sure if this was indeed the
theory behind the modular construction. It looks pretty impressive
when the cover is removed, though.

Anyhow, the tuner I purchased initially lit up when powered on, but
just a few minutes later it was DOA. I decided to bite the bullet and
have it repaired. Well, $177 later, I have a working tuner. There is
a lesson there somewhere about buying untested tuners on eBay, but
since the purchase price was so low, I didn't feel ripped off in any
way. What was annoying was that in addition to blown fuses and a
faulty diode, there were some transistors supposedly missing from the
tuner - perhaps it had been long ago cannibalized for parts? Hard to
know the history of a 25 year old piece of equipment. I didn't
perform the work myself (no skills) - I had it done by a fairly
reputable repair facility called the Audio-Video Shoppe in Culver
City, California. They seemed competent and relatively straight with
me, and included a plastic baggie with all the blown components they
supposedly replaced when I picked up the tuner. They warranty their
work for 90 days.

So I just got it back, and I have to say that I am VERY impressed with
how this tuner sounds. Granted I don't have a tremendous basis for
comparison - for many years I used the tuner section of a
Carver 900 receiver, which I think was quite sensitive - very good at
pulling in weak stations, but seemed to roll off the high frequencies
a bit. Recently I bought the much acclaimed Onkyo Integra T-9090-II
based on its stellar specs. I thought it sounded a little fuller than
the Carver (I couldn't actually A-B them for a direct comparison) but
I couldn't stand all the tiny lights and buttons (a very late eighties
digital design cosmetically, and therefore not to my taste at all).
So I sold the Onkyo after only a few days - I hardly listened to it at
all because I didn't enjoy using it or looking at it (a bit silly, I
know).

Well, this Harman/Kardon doesn't have great specs by 2002 standards,
but it is the best sounding tuner I've ever had in my listening room.
A much more detailed and forward soundstage than the digital tuners I
have heard, and a very 'lively' sound, particularly on piano notes,
which have a nice bounce and jump to them - a pleasant surprise. Bass
is nicely defined without being too up front, and highs are sharp and
clear. Vocals sound great, with maybe just a faint trace of sibilance
in the highs, but not much a problem to my ear. Overall a very clean
and inviting sound.

The Citation 18 seems sensitive enough to pull in weak signals cleanly
and in stereo. A few of the weaker stereo stations in my area came in
a little bit hissy, though there is a noise filter activated by a
button on the front panel that cuts this hiss quite dramatically.
This definitely doesn't seem to be needed on stronger stations, as
this tuner sounds very quiet to me on those. Can't really speak to
its selectivity, as I haven't experimented with that much, and it
isn't much of an issue in my area.

Construction is extremely robust, with thick aluminum faceplate, and a
hefty weight of 23 lbs or so. It is easy to tune, and to my eye has a
nice appearance, although the horizontal wheel used to tune in
stations seems definitely to have been 'borrowed' from the good folks
at Marantz. The tuning meter takes a little getting used to, as it is
backwards from what I'm used to - as the needle goes further to the
right it signifies a weaker signal, not a stronger one. It is easy
enough to use once you get acclimated to it, though.

On the whole my initial impressions of this tuner are quite favorable,
and I feel as though I'll probably hang on to it for a while. I'd be
curious if anyone has a copy of the owner's manual, as I'm a little
confused about a few of the controls. I'd also like to hear about any
firsthand experiences with this tuner, and how people think it
compares sonically to its competitors from Kenwood, Sansui, Marantz,
MacIntosh, Accuphase, etc. Look forward to hearing from you guys...


Accuphase t109v

donroth45
 

Would like to hear from folks who actually own this
tuner what their experiences are and how they would
compare it to prior-owned supertuners.

Accuphase sort of reminds me of the japanese tandberg
in the sense that they make very high-quality products
but have relatively-poor resale value. I have never
figured this one out. At least that is my impression
when looking at some of the prices of used accuphase
equipment being offered.

Don

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Re: My sansui TU-9900

aa6zd <k6kc@...>
 

--- In FMtuners@y..., Charles Peterson <charlesp@d...> wrote:

Hi, thank you for your reply. My apologies if I was not clear
about
this thin clear layer. This is not on the componets side. This
sticky
stuff is on the bottom (traces side). Boards F-2527( power
supply)
and F-2539( AM IF Circuit )have more of this.
Sounds like some one has sprayed a coating on the bottom, that was
incorrect. It is typical that boards are "sealed" once built and
tested, to seal and preserve the copper/tin plated traces from
corrosion in tropical environments. Usually this is a thin coating
of
clear or greenish clear colored hard substance. But I have also
seen
cases, once on older tube gear, where this hard substance turns
soft
and gooey over a long time. Sounds like the factory goofed, they
or

There is nothing sticky or gooey on the bottom side of my TU-9900
either,
though the boards do look shinier than from the top. The bottom
sides of the
boards are covered in a hard shiny green plastic which covers all
the foil
traces, but not necessarily the soldering joints. I noticed no
particular
smell (other than a trace of old capacitor, probably coming from the
top side).

It does sound to me like someone applied some sort of "treatment"
probably for
no good reason. Such treatments as might properly be applied (like
microdrops
of Dexoit to the condenser grounds) should only be applied to tiny
points very
carefully. If the treatment has only been applied to the bottom
sides of the
circuit boards, it might not be particularly harmful to operation,
except for
the smell.

I don't think the factory green plastic would have degraded into
something
smelly and gooey, but if very harsh humidity and heat caused to
factory coating
to come off, the raw phenolic surface underneath might become sticky
and gooey
under those conditions. Before cleaning, you should see if the
factory green
plastic is still there underneath the sticky surface. If not,
cleaning might be
perilous.
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Gentlemen,
The "hard greenish" coating that is being found on the trace-side of
these circuit boards is not applied to seal the board. In the PC
board industry, it is referred to as "solder mask".
It is typically a two-part, photosensitive ink. Translucent green is
the most common color, though it comes in other colors. It is applied
to the solder side of the board, prior to the board undergoing
automated 'wave' soldering. The solder bath does not adhere to the
PCB in the areas that are coated with the mask. If one notes, there
will be none of the green material where a component lead comes
through the board to a solder pad.
As others have mentioned, that coating does not account for what
has been discovered on the 9900's PCB's in question. Solder mask,
in my experience exhibits no stickyness, once cured.
One form of coating that does have a certain 'tacky' property, is
the thick 'conformal' coatings, that are commonly found on aerospace
and military PCB's, both on the trace side and component side. These
can range from thin spray coatings, just thick enough to seal out
moisture, to dipped coatings, which virtually encapsulate the
components on the board. These coatings typically remain
semi-flexible, and will 'give' to the pressure of one's fingernail.
Troubleshooting/repairing boards so coated can be a real challenge.
As has been suggested, perhaps some 'aftermarket' conformal coating
has been applied to the solder side of the 9900's boards. The odor
problem may be unrelated to the coating, but as mentioned before, may
just be some typical 'electrolyte stinch', from the caps. Also, it
has always been my notion that consumer electronic gear of asian
origin has a distinctive (internal) odor, both when new, and while
operating, that I don't detect in 'domestically' produced gear. A
pure guess is a difference in the chemical formulations used in
circuit board fabrication.
Were it mine, I'd first try a clean up, without actually doing a
wholesale removal of the coating, which could evolve into quite a
mess. The dielectric properties of the coating have apparently not
harmed the unit's performance.
BTW, if anyone would like to play with some of the 'solder mask', I
have a pile of it in the warehouse, for the cost of shipping. It
should be used with caution, as the fumes are quite potent!
Good listening,
Lowell
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++


Latest on IBOC digital FM

Mike Zuccaro
 

Guys:
From this weeks "Radio World":

Ibiquity Digital Corp will be rolling it out at the 2002 NAB convention. 3
transmitter manufacturers- Harris, Broadcast Electronics, and Nautel, will be
showing IBOC transmitters. Infinity Broadcasting has tested it so far in 5
cities on 5 stations.

Cost of changeover for xmtr facilities to be between $27k-250k per station.

We'll see what happens.

Best,
mike Z.


Re: What Tuner to buy new today?

sedond <dsedon@...>
 

hi john,

did i ask ya if ya have compared these to the b261, as far as sonics
go? i have a b760 in the basement that has yet to get hooked up; i
yust today was the high bidder on another one from europe - the price
was too good to pass up, especially since one yust sold on ebay for
~$1200, from canada.

the b261 is actually an excellent-sounding tuna - i prefer the
slightly warmer sound of my onix, but either one will smoke the sonics
of an etude, imo... the b261 can be operated w/a remote, also...

doug s.

--- In FMtuners@y..., "John M. Tooley" <jmtooley@c...> wrote:
I have three ReVox B760's if you are interested in taking one off my
hands. The one for sale had a complete going through the other month a
both meters were replaced. These were almost $1700 each in their day.

John
----- Original Message -----
From: reb1208
To: FMtuners@y...
Sent: Monday, April 01, 2002 2:00 PM
Subject: [FMtuners] Re: What Tuner to buy new today?


--- In FMtuners@y..., "newaag" <newaag@y...> wrote:
> Here is a review of the ST-6000
>
> If you have the $, go for a Accuphase T-109 ot T-109v
>
> http://www.tnt-audio.com/sorgenti/marantz-st6000_e.html
>
> Specs are a little weak compared to most good units, i.e.
distortion
> and signal to noise.

I just looked into the Accuphase. $3,300 retail is too rich for my
blood. My limit is 2k tops with remote. Anyway about the Marantz
6000T. Don Scott is selling his own modified version for I think
$625. But now that i see what this unit looks like inside, I've
lost
all interest. That Classe Audio tuner I had was good but I hated
the
fact that it was on all the time unmuted. Problems with bleed thru
in
the pre-amp and heaven help you if you had the volume up and
selected
the tuner position by mistake. Say goodbye to your speakers.
Bob



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Re: Any experience/info re: Harman/Kardon Citation 18 tuner?

Mike Zuccaro
 

In a message dated 4/5/02 5:51:05 PM Pacific Standard Time,
blundry@mediaone.net writes:

<< al, as I'm a little
confused about a few of the controls. I'd also like to hear about any
firsthand experiences with this tuner, and how people think it
compares sonically to its competitors from Kenwood, Sansui, Marantz,
MacIntosh, Accuphase, etc. Look forward to hearing from you guys...
>>
Nameless guy:
If you like it, that's what counts. Nice tuner, I've worked on a few of
them. You will find it should fill you every need, and the money you spent on
the fix was well spent. It would cost far more than that to make that tuner
today. Always assume whatever you buy used, on ebay or garage sales or
swapmeets, or whatever, will need some (or a lot!) of repiar unless you've
checked it out first, or it's sold with a guarantee.

Got a name,or did you mother name you Blundry?
best,
Mike Zuccaro


Re: More on KT-8300 op amp upgrades

Mike Zuccaro
 

In a message dated 4/4/02 10:14:48 PM Pacific Standard Time, newaag@yahoo.com
writes:

<< 20kohm. You want to try soldering
a 10 to 100 pF cap directly across the leads of these 4 feedback
resistors listed above. For experimenting, use any cap available,
even ceramic. If this improves the sound, you have eliminated a high
frequency problem, most likely oscill >>
And very short leads- at 100mc even small caps can be resonant. Bad news.
Use the smallest micas you can find.
MZ


Re: Marantz 10B IF Filter Module Frequency Response?

Mike Zuccaro
 

In a message dated 4/4/02 3:27:19 PM Pacific Standard Time,
jbyrns@enteract.com writes:

<<
1.) Are all six filter modules identical, or are there several
different types used in the tuner?

2.) What are the frequency response characteristics of an individual
filter module as installed in the tuner?

Thanks, >>

John:
1- Yes, identical
2- Some time ago I swept one- about 350 kc wide, not perfectly flat. Dont
forget that there are 6 in series, the bandwith reduction factor gets it down
to about 225kc.

best
Mike Z.


Re: My sansui TU-9900

Mike Zuccaro
 

In a message dated 4/4/02 12:59:21 PM Pacific Standard Time,
charlesp@darwin.sfbr.org writes:

<< ded to remove the bottom metal cover and
> take a look inside. Well, looked like every part and soldering was
> original from the factory. The thing I did not understand was this
> sticky thin clear layer all over the PC boards. I put my fingers and
> touched it last night. Well, I washed my hands five times but this
> smell is still on my fingers. >>

No big deal- some Japanese products had a layer of clear anti-oxidant to keep
the exposed copper traces from corroding. Usually not on the front end,
though it's not impossible. It can be removed with pure 100% alcohol, but if
it works to your satisfaction, dont touch it!
Best,
Mike Z