[R-390] R-390 Digest, Vol 83, Issue 29

wa4aos at aol.com wa4aos at aol.com
Thu Mar 10 12:32:07 EST 2011


 


 I am not surprised by the discoloration of the brass gears or the aluminum

plate during a soaking in any solution that does not have a neutral pH.



Brass and Bronze are more cathodic than aluminum (.4 V compared to .9 V).

Since the parts were soaked together you will get a current flow (~.5 V)

between the dissimilar metals and it will show up as discoloring at first

and eventually at wholesale corrosion (pitting, ultimate dissolution) if

left that way for any time.



With any sorts of acid of alkali cleaning solutions you should only wash

components of a similar chemical make-up together. Even the bronze bushings

in an aluminum panel will begin to react and eat away at the aluminum as

aluminum is "sacrificial" to a more noble metal (gold, silver, nickel,

copper, bronze and brass).



Alkali earth metals (anodic) like magnesium, zinc, aluminum, etc... will go

into solution and plate out on a noble metal. This can be an acidic, alkali

or salt solution. As you mentioned we do not know if any of the cleaning

solutions are at a perfect pH of 7.0 or if they stay there as contaminants

build up in the bath.



-- 



 Hi Tish,

Thanks for the chemistry lesson. It has been too many years since I cracked a chemistry book while in engineering school..
One thing I really appreciate is all of the knowledge brought to the table from members of this forum.
I have been working on R 390, R 390A and R 392 receivers as an early retirement business for a number of years.  I learn 
neat stuff often from the users of this group often. 
Many thanks to those who contribute information that benefits us all..

73,
Glenn WA4AOS
DSM Labs

 


 

 

-----Original Message-----
From: r-390-request <r-390-request at mailman.qth.net>
To: r-390 <r-390 at mailman.qth.net>
Sent: Thu, Mar 10, 2011 11:49 am
Subject: R-390 Digest, Vol 83, Issue 29


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Today's Topics:



   1. Re: My 2 cents regarding cleaning RF decks (Barry Williams)

   2.  My 2 cents regarding cleaning RF decks (Tisha Hayes)

   3. Re: My 2 cents regarding cleaning RF decks (Curt Nixon)

   4. Re: My 2 cents regarding cleaning RF decks

      (ToddRoberts2001 at aol.com)

   5. Re: My 2 cents regarding cleaning RF decks (Mike Carroll)

   6. Re: My 2 cents regarding cleaning RF decks (Shoppa, Tim)

   7. Re: Tisha  AKA  Processchick62 (John Flood)





----------------------------------------------------------------------



Message: 1

Date: Thu, 10 Mar 2011 10:01:16 -0600

From: Barry Williams <ba.williams at charter.net>

Subject: Re: [R-390] My 2 cents regarding cleaning RF decks

To: r-390 at mailman.qth.net

Message-ID: <4D78F5CC.8010500 at charter.net>

Content-Type: text/plain; charset=ISO-8859-1; format=flowed



It may be time to try an old crockpot with antifreeze. Set the temp to 

the lowest setting. Do this outside for 8-12 hours. It is safe for 

aluminum too. Just remember the fumes are toxic, and so is the crockpot 

after you do this.  If you stole it and plan to sneak it back into the 

kitchen- don't!



Anyway, the crockpot method will remove a lot of seemingly impossible to 

remove crud. It isn't corrosive like Simple Green that people still 

think is magic juice.





the other other Barry



> Hi Tish,

>

> I have a Sharper Tec 5 gallon Ultrasonic cleaner. One of those $1500 

commercial units that will take the solvent temp up to 140F.

>

> When I bought this cleaner I had hoped to dunk the nose of the entire RF decks 

from R 390 and R 390A's into the bath and clean without removing the gears.

> I had several badly damaged RF decks that were NOT candidates for resurrection 

to test with.

>

> I tried Purple Power first and had disastrous results. At 140F the Aluminum 

face plate on front of an R390A RF deck turned black in less

>   than 20 minutes. The brass gears became tarnished and Hash marks for 

alignment as well as the serial number info disappeared..

>

> Next I tried Simple Green and had similar results but not as bad. The gears 

did start to tarnish and the Aluminum plate did start to turn dark.

> The hash marks held up a little better but were starting to fade.

>

> I have not checked the PH of those cleaners but my guess is they are alkaline 

and that probably accounted for the Aluminum reaction.

> Not being a chemist, I am not sure what happened with the brass.

>

> Now I use a Toluene based cleaner called RS 8 that I bought from Sharper Tec, 

the company that made my cleaner; It cost $200 for 5 gallons. I heat the tank up 

until it reaches

>   100F and put my basket of gears and parts  in the soup with gears removed 

and the RF electronics chassis removed from the RF frame of a 390A RF deck. Yes, 

with a little

> work, I remove the gear frame from the chassis containing the electronics and 

put the frame in the cleaner.. It would be difficult if not impossible to take 

the frame completely apart since the hash

> mark cams are pressed onto the frame and provide the alignment foundation of 

the entire deck.

>

> Even though I still remove the gears I am additionally able to clean all of 

the shafts, cams and fittings that are permanently attached to the frame.

> I have done this enough times that I can take the RF deck apart down to the 

frame and put it back together in about an hour and a half, less cleaning time, 

Once I have pulled the RF deck from a 390A. It is more

> work but afterwards, I know ALL of the grime and crud is fully removed from 

places on the frame that are impossible to reach otherwise; just because it's 

difficult to reach parts of the RF deck

> does not mean there is not crud there as well

>   First time I pulled the 39OA deck apart, down to the frame and re assembled 

it,

> I spend about 6 to 7 hours figuring out how to do everything; that was with 

many digital pics I took to help reverse my steps.

>

> I have had no reactions with the toluene product but I don't leave the parts 

in the cleaner more than 30 minutes at 100F.That seems to be the maximum time 

required for a very good cleaning with my cleaner.

>

> 73,

> Glenn Scott WA4AOS

> DSM Labs

>

>

>

>

>

>

>

>

>

> ______________________________________________________________

> R-390 mailing list

> Home: http://mailman.qth.net/mailman/listinfo/r-390

> Help: http://mailman.qth.net/mmfaq.htm

> Post: mailto:R-390 at mailman.qth.net

>

> This list hosted by: http://www.qsl.net

> Please help support this email list: http://www.qsl.net/donate.html

>







------------------------------



Message: 2

Date: Thu, 10 Mar 2011 10:12:33 -0600

From: Tisha Hayes <tisha.hayes at gmail.com>

Subject: [R-390]  My 2 cents regarding cleaning RF decks

To: r-390 at mailman.qth.net

Message-ID:

	<AANLkTinuD2cTVwae+J9C+-QBbLw_KD9Vw8nypnDgUvt4 at mail.gmail.com>

Content-Type: text/plain; charset=ISO-8859-1



 I am not surprised by the discoloration of the brass gears or the aluminum

plate during a soaking in any solution that does not have a neutral pH.



Brass and Bronze are more cathodic than aluminum (.4 V compared to .9 V).

Since the parts were soaked together you will get a current flow (~.5 V)

between the dissimilar metals and it will show up as discoloring at first

and eventually at wholesale corrosion (pitting, ultimate dissolution) if

left that way for any time.



With any sorts of acid of alkali cleaning solutions you should only wash

components of a similar chemical make-up together. Even the bronze bushings

in an aluminum panel will begin to react and eat away at the aluminum as

aluminum is "sacrificial" to a more noble metal (gold, silver, nickel,

copper, bronze and brass).



Alkali earth metals (anodic) like magnesium, zinc, aluminum, etc... will go

into solution and plate out on a noble metal. This can be an acidic, alkali

or salt solution. As you mentioned we do not know if any of the cleaning

solutions are at a perfect pH of 7.0 or if they stay there as contaminants

build up in the bath.



-- 

Ms. Tisha Hayes/ AA4HA

----------------

"I'll be a diode, cathode, electrode

Overload, generator, oscillator

Make a circuit with me." -- The Polecats





------------------------------



Message: 3

Date: Thu, 10 Mar 2011 11:18:53 -0500

From: Curt Nixon <cptcurt at flash.net>

Subject: Re: [R-390] My 2 cents regarding cleaning RF decks

To: Barry Williams <ba.williams at charter.net>

Cc: r-390 at mailman.qth.net

Message-ID: <4D78F9ED.50403 at flash.net>

Content-Type: text/plain; charset=ISO-8859-1; format=flowed



As a model airplane engine cleaner, many of us have used the crockpot 

with antifreeze.  It will indeed clean up the worst cases of baked on 

castor oil which acetone, lacquer thinner, etc will not even touch.



I HAVE had it turn aluminum engine castings dark however.  It seems that 

parts like 6061 material (machined parts) are ok and come out 

bright..castings that are alloyed with ? sometimes react and turn dark.



Curt

KU8L





Barry Williams wrote:

> It may be time to try an old crockpot with antifreeze. Set the temp to 

> the lowest setting. Do this outside for 8-12 hours. It is safe for 

> aluminum too. Just remember the fumes are toxic, and so is the crockpot 

> after you do this.  If you stole it and plan to sneak it back into the 

> kitchen- don't!

>

> Anyway, the crockpot method will remove a lot of seemingly impossible to 

> remove crud. It isn't corrosive like Simple Green that people still 

> think is magic juice.

>

>

> the other other Barry

>

>   

>> Hi Tish,

>>

>> I have a Sharper Tec 5 gallon Ultrasonic cleaner. One of those $1500 

commercial units that will take the solvent temp up to 140F.

>>

>> When I bought this cleaner I had hoped to dunk the nose of the entire RF 

decks from R 390 and R 390A's into the bath and clean without removing the 

gears.

>> I had several badly damaged RF decks that were NOT candidates for 

resurrection to test with.

>>

>> I tried Purple Power first and had disastrous results. At 140F the Aluminum 

face plate on front of an R390A RF deck turned black in less

>>   than 20 minutes. The brass gears became tarnished and Hash marks for 

alignment as well as the serial number info disappeared..

>>

>> Next I tried Simple Green and had similar results but not as bad. The gears 

did start to tarnish and the Aluminum plate did start to turn dark.

>> The hash marks held up a little better but were starting to fade.

>>

>> I have not checked the PH of those cleaners but my guess is they are alkaline 

and that probably accounted for the Aluminum reaction.

>> Not being a chemist, I am not sure what happened with the brass.

>>

>> Now I use a Toluene based cleaner called RS 8 that I bought from Sharper Tec, 

the company that made my cleaner; It cost $200 for 5 gallons. I heat the tank up 

until it reaches

>>   100F and put my basket of gears and parts  in the soup with gears removed 

and the RF electronics chassis removed from the RF frame of a 390A RF deck. Yes, 

with a little

>> work, I remove the gear frame from the chassis containing the electronics and 

put the frame in the cleaner.. It would be difficult if not impossible to take 

the frame completely apart since the hash

>> mark cams are pressed onto the frame and provide the alignment foundation of 

the entire deck.

>>

>> Even though I still remove the gears I am additionally able to clean all of 

the shafts, cams and fittings that are permanently attached to the frame.

>> I have done this enough times that I can take the RF deck apart down to the 

frame and put it back together in about an hour and a half, less cleaning time, 

Once I have pulled the RF deck from a 390A. It is more

>> work but afterwards, I know ALL of the grime and crud is fully removed from 

places on the frame that are impossible to reach otherwise; just because it's 

difficult to reach parts of the RF deck

>> does not mean there is not crud there as well

>>   First time I pulled the 39OA deck apart, down to the frame and re assembled 

it,

>> I spend about 6 to 7 hours figuring out how to do everything; that was with 

many digital pics I took to help reverse my steps.

>>

>> I have had no reactions with the toluene product but I don't leave the parts 

in the cleaner more than 30 minutes at 100F.That seems to be the maximum time 

required for a very good cleaning with my cleaner.

>>

>> 73,

>> Glenn Scott WA4AOS

>> DSM Labs

>>

>>

>>

>>

>>

>>

>>

>>

>>

>> ______________________________________________________________

>> R-390 mailing list

>> Home: http://mailman.qth.net/mailman/listinfo/r-390

>> Help: http://mailman.qth.net/mmfaq.htm

>> Post: mailto:R-390 at mailman.qth.net

>>

>> This list hosted by: http://www.qsl.net

>> Please help support this email list: http://www.qsl.net/donate.html

>>

>>     

>

> ______________________________________________________________

> R-390 mailing list

> Home: http://mailman.qth.net/mailman/listinfo/r-390

> Help: http://mailman.qth.net/mmfaq.htm

> Post: mailto:R-390 at mailman.qth.net

>

> This list hosted by: http://www.qsl.net

> Please help support this email list: http://www.qsl.net/donate.html

>

>   







------------------------------



Message: 4

Date: Thu, 10 Mar 2011 11:21:01 -0500 (EST)

From: ToddRoberts2001 at aol.com

Subject: Re: [R-390] My 2 cents regarding cleaning RF decks

To: r-390 at mailman.qth.net

Message-ID: <580fd.4b436207.3aaa546d at aol.com>

Content-Type: text/plain; charset="US-ASCII"



I have always had good results over the  years by soaking an RF Deck

in a tub of Kerosene for several days.  Periodically I will swish around the

gears and shafts with a paintbrush or  toothbrush if needed to help loosen

the dried up grime. Let the Kerosene sit  for a day without disturbing it

at the end so the sand and grime will settle  to the bottom of the tub. A 

fresh

rinse with clean Kerosene at the end will  insure no sand or dirt remains.

The Kerosene can be recycled by pouring it  through a good filter.



Always be sure and remove the RF Deck  transformers  before soaking in 

Kerosene.

The transformers have the  small ceramic trimmers inside. The trimmers have

some kind of rubber or  plastic gasket inside that will swell up if soaked 

in

Kerosene for several  days. I found that out the hard way!



Otherwise the Kerosene appears to be  harmless to all other electronic

components like inductors, capacitors and  resistors plus the Kerosene is

non-conductive so it will not short out  anything or cause corrosion

like traces of water could do if left  behind.



After a good soaking I place the cleaned RF Deck on a towel in  front of a 

dehumidifier for a few days until it is bone dry then be sure to  lubricate 

all

moving parts, shafts and bearings with Mobil 1 Synthetic  

before and during reassembly and before use.



73 - Todd WD4NGG  







------------------------------



Message: 5

Date: Thu, 10 Mar 2011 11:23:26 -0500

From: Mike Carroll <mike at lacperdu.com>

Subject: Re: [R-390] My 2 cents regarding cleaning RF decks

To: r-390 at mailman.qth.net

Message-ID: <4D78FAFE.3030303 at lacperdu.com>

Content-Type: text/plain; charset=ISO-8859-1; format=flowed



On 3/10/2011 10:13 AM, wa4aos at aol.com wrote:

> Hi Tish,

>

> I have a Sharper Tec 5 gallon Ultrasonic cleaner. One of those $1500 

commercial units that will take the solvent temp up to 140F.

>

> When I bought this cleaner I had hoped to dunk the nose of the entire RF decks 

from R 390 and R 390A's into the bath and clean without removing the gears.

> I had several badly damaged RF decks that were NOT candidates for resurrection 

to test with.

>

> I tried Purple Power first and had disastrous results. At 140F the Aluminum 

face plate on front of an R390A RF deck turned black in less

>   than 20 minutes. The brass gears became tarnished and Hash marks for 

alignment as well as the serial number info disappeared..

>

> Next I tried Simple Green and had similar results but not as bad. The gears 

did start to tarnish and the Aluminum plate did start to turn dark.

> The hash marks held up a little better but were starting to fade.

>

> I have not checked the PH of those cleaners but my guess is they are alkaline 

and that probably accounted for the Aluminum reaction.

> Not being a chemist, I am not sure what happened with the brass.

>

> Now I use a Toluene based cleaner called RS 8 that I bought from Sharper Tec, 

the company that made my cleaner; It cost $200 for 5 gallons. I heat the tank up 

until it reaches

>   100F and put my basket of gears and parts  in the soup with gears removed 

and the RF electronics chassis removed from the RF frame of a 390A RF deck. Yes, 

with a little

> work, I remove the gear frame from the chassis containing the electronics and 

put the frame in the cleaner.. It would be difficult if not impossible to take 

the frame completely apart since the hash

> mark cams are pressed onto the frame and provide the alignment foundation of 

the entire deck.

>

> Even though I still remove the gears I am additionally able to clean all of 

the shafts, cams and fittings that are permanently attached to the frame.

> I have done this enough times that I can take the RF deck apart down to the 

frame and put it back together in about an hour and a half, less cleaning time, 

Once I have pulled the RF deck from a 390A. It is more

> work but afterwards, I know ALL of the grime and crud is fully removed from 

places on the frame that are impossible to reach otherwise; just because it's 

difficult to reach parts of the RF deck

> does not mean there is not crud there as well

>   First time I pulled the 39OA deck apart, down to the frame and re assembled 

it,

> I spend about 6 to 7 hours figuring out how to do everything; that was with 

many digital pics I took to help reverse my steps.

>

> I have had no reactions with the toluene product but I don't leave the parts 

in the cleaner more than 30 minutes at 100F.That seems to be the maximum time 

required for a very good cleaning with my cleaner.

>

> 73,

> Glenn Scott WA4AOS

> DSM Labs

>

>

>

>

>

>

>

>

>

> ______________________________________________________________

> R-390 mailing list

> Home: http://mailman.qth.net/mailman/listinfo/r-390

> Help: http://mailman.qth.net/mmfaq.htm

> Post: mailto:R-390 at mailman.qth.net

>

> This list hosted by: http://www.qsl.net

> Please help support this email list: http://www.qsl.net/donate.html

>

Glenn:



I'll add my one cent.



LRultrasonics.com ;   Application bulletin #46 covers television tuners, 

whatever they are.  They recommend 3-5 minutes cleaning time, followed 

by a cycle in their "Instrument Rinsing Solution"   No recommended 

cleaning cycle seems longer than 10 minutes.  If anyone chooses to go 

this route, Follow their directions explicitly.   I skimmed, rather than 

read their directions,  and stuck my favorite 1911 slide solidly to the 

frame.  Much weeping and gnashing of the teeth.

Mike





------------------------------



Message: 6

Date: Thu, 10 Mar 2011 11:32:27 -0500

From: "Shoppa, Tim" <tshoppa at wmata.com>

Subject: Re: [R-390] My 2 cents regarding cleaning RF decks

To: "ToddRoberts2001 at aol.com" <ToddRoberts2001 at aol.com>,

	"r-390 at mailman.qth.net" <r-390 at mailman.qth.net>

Message-ID:

	<B136EDE3DF5EC441B6F08E0A7AB872450BB0D13F10 at EX2K7-CMS-1.wmata.local>

Content-Type: text/plain; charset="us-ascii"



"Me too" for the Kerosene, especially for blue/yellow stripers. (Not sure what 

level of cleanliness others are aiming for but removing the layers of grimed up 

sand was my priority.)



-----Original Message-----

From: r-390-bounces at mailman.qth.net [mailto:r-390-bounces at mailman.qth.net] On 

Behalf Of ToddRoberts2001 at aol.com

Sent: Thursday, March 10, 2011 11:21 AM

To: r-390 at mailman.qth.net

Subject: Re: [R-390] My 2 cents regarding cleaning RF decks



I have always had good results over the  years by soaking an RF Deck

in a tub of Kerosene for several days.  Periodically I will swish around the

gears and shafts with a paintbrush or  toothbrush if needed to help loosen

the dried up grime. Let the Kerosene sit  for a day without disturbing it

at the end so the sand and grime will settle  to the bottom of the tub. A 

fresh

rinse with clean Kerosene at the end will  insure no sand or dirt remains.

The Kerosene can be recycled by pouring it  through a good filter.



Always be sure and remove the RF Deck  transformers  before soaking in 

Kerosene.

The transformers have the  small ceramic trimmers inside. The trimmers have

some kind of rubber or  plastic gasket inside that will swell up if soaked 

in

Kerosene for several  days. I found that out the hard way!



Otherwise the Kerosene appears to be  harmless to all other electronic

components like inductors, capacitors and  resistors plus the Kerosene is

non-conductive so it will not short out  anything or cause corrosion

like traces of water could do if left  behind.



After a good soaking I place the cleaned RF Deck on a towel in  front of a 

dehumidifier for a few days until it is bone dry then be sure to  lubricate 

all

moving parts, shafts and bearings with Mobil 1 Synthetic  

before and during reassembly and before use.



73 - Todd WD4NGG  



______________________________________________________________

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Home: http://mailman.qth.net/mailman/listinfo/r-390

Help: http://mailman.qth.net/mmfaq.htm

Post: mailto:R-390 at mailman.qth.net



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------------------------------



Message: 7

Date: Thu, 10 Mar 2011 08:47:27 -0800 (PST)

From: John Flood <kb1fqg at yahoo.com>

Subject: Re: [R-390] Tisha  AKA  Processchick62

To: Larry WA9VRH <wa9vrh at dishmail.net>, rbethman

	<rbethman at comcast.net>,	r-390 at mailman.qth.net

Cc: tisha.hayes at gmail.com

Message-ID: <228777.20571.qm at web84106.mail.mud.yahoo.com>

Content-Type: text/plain; charset=iso-8859-1



Hi Larry



Easy to see how if you hadn't seen the thread it might not look so good!? No 

worries, it's safe to start your car!



John?









----- Original Message ----

> From: Larry WA9VRH <wa9vrh at dishmail.net>

> To: rbethman <rbethman at comcast.net>; r-390 at mailman.qth.net

> Cc: John Flood <kb1fqg at yahoo.com>; tisha.hayes at gmail.com

> Sent: Wed, March 9, 2011 7:14:48 PM

> Subject: Re: [R-390] Tisha AKA Processchick62

> 

> Hi Bob and all,

> 

> Guess I needed to go back to the beginning of the thread..

> 

> Please excuse myself while I get my foot out of my mouth!

> 

> 73 Larry WA9VRH

> 

> 

> ----- Original Message ----- From: "rbethman" <rbethman at comcast.net>

> To: <r-390 at mailman.qth.net>

> Cc: "John Flood" <kb1fqg at yahoo.com>; "Larry WA9VRH" <wa9vrh at dishmail.net>

> Sent: Wednesday, March 09, 2011 6:05 PM

> Subject: Re: [R-390] Tisha AKA Processchick62

> 

> 

> > Having conversed direct by messages with Tisha, I CAN say that she has a 

>GREAT sense of humor!

> > 

> > I also don't see ANYTHING wrong with John's post!

> > 

> > I can only suggest that perhaps there are a list member or two that really 

>needs to loosen their shorts.? Too much tension in that area creates headaches 

>and extraneous pains, not to mention the requisite "attitude adjustment" that 

>appears necessary.? (IMHO)? (LOL!)

> > 

> > Bob - N0DGN

> > 

> > On 3/9/2011 6:20 PM, John Flood wrote:

> >> If so, no one to blame but myself.? Then again Tisha wasn't asking a "real"

> >> question.? In case you did not know, what she sent was a copy of a fake

> >> audiophool question sent to an Ebay seller with a crazy listing for a pair 

>of

> >> "Matched" ballast tubes.? Many list persons were poking fun at it.? If I 

>have

> >> offended Tisha, I respectfully submit my humble apology to her here and 

now.

> >> 

> >> John

> >> 

> >> 

> >> 

> >> ----- Original Message ----

> >>> From: Larry WA9VRH<wa9vrh at dishmail.net>

> >>> To: John Flood<kb1fqg at yahoo.com>

> >>> Sent: Wed, March 9, 2011 6:06:06 PM

> >>> Subject: Re: [R-390] Tisha AKA Processchick62

> >>> 

> >>> What a dunbass answer!!? Hope they throw you off the list!

> >>> Larry WA9VRH

> >>> 

> >>> ----- Original Message ----- From: "John Flood"<kb1fqg at yahoo.com>

> >>> To:<r-390 at mailman.qth.net>

> >>> Sent: Wednesday, March 09, 2011 12:24 PM

> >>> Subject: [R-390] Tisha AKA Processchick62

> >>> 

> >>> 

> >>> When Tisha sends text like that, me wife gets jellous!

> >>> 

> >>> :)

> >>> 

> >>> John Flood

> >>> KB1FQG

> >>> 

> >>> ----- Original Message ----

> >>>> From: Tisha Hayes<tisha.hayes at gmail.com>

> >>>> To: r-390 at mailman.qth.net

> >>>> Sent: Wed, March 9, 2011 12:00:10 PM

> >>>> Subject: [R-390] Ballast Tube Folly

> >>>> 

> >>>> *Dear ppafsn,*

> >>>> 

> >>>> Hi! I am really interested in buying a matched set. Can you tell me what 

>the

> >>>> percentage of running resistance is on the tubes? Also, have you checked 

>the

> >>>> elements with a microscope to identify any marsentite at the connection

> >>>> joints. Real collectors would want to know if the tubes can run in a

> >>>> push-pull configuration to minimize the total harmonic distortion of the

> >>>> amplifier.

> >>>> 

> >>>> - processchick62

> >>>> 

> >>>> *I am awaiting his professional opinion, so valuable when making that

> >>>> purchasing decision.*

> >>>> 

> >>>> Tisha Hayes

> >>>> ______________________________________________________________

> >>>> R-390 mailing list

> >>>> Home: http://mailman.qth.net/mailman/listinfo/r-390

> >>>> Help: http://mailman.qth.net/mmfaq.htm

> >>>> Post: mailto:R-390 at mailman.qth.net

> >>>> 

> >>>> This list hosted by: http://www.qsl.net

> >>>> Please help support this email list: http://www.qsl.net/donate.html

> >>>> 

> >>> ______________________________________________________________

> >>> R-390 mailing list

> >>> Home: http://mailman.qth.net/mailman/listinfo/r-390

> >>> Help: http://mailman.qth.net/mmfaq.htm

> >>> Post: mailto:R-390 at mailman.qth.net

> >>> 

> >>> This list hosted by: http://www.qsl.net

> >>> Please help support this email list: http://www.qsl.net/donate.html

> >>> 

> >> ______________________________________________________________

> >> R-390 mailing list

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> > 

> > -- +------------------------------------------------------------------+

> > |? ? ? ? ? ? ? AM Amateur Radio Operator? ? N?DGN? ? ? ? ? ? ? ? |

> > +------------------------------------------------------------------+

> > |? ? ? ? ? ? ? http://home.comcast.net/~rbethman/? ? ? ? ? ? ? ? |

> > +------------------------------------------------------------------+

> > | Bob Bethman? ? ? ? ? ? ? ? \\\|///? ? " The absence of a danger |

> > |? ? ? ? ? ? ? ? ? ? ? ? ? \\ ~ ~ //? ? ? signal does *NOT* mean? |

> > | rbethman at comcast.net? ? ? (/ @ @ /)? ? ? that everything is OK " |

> > +----------------------o00o---?(_)?---o00o-------------------------+

> > 

> 

> 





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End of R-390 Digest, Vol 83, Issue 29

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