[R-390] R-390 Digest, Vol 82, Issue 18/ 12V tap
Henry Mei'l's
meils at get2net.dk
Fri Feb 18 20:09:52 EST 2011
There's a 12 volt tap on the power transformer -- I used it on my first
R-390A when my ballast tube went West.
Henry,
OZ3O N2NR
----- Original Message -----
From: <r-390-request at mailman.qth.net>
To: <r-390 at mailman.qth.net>
Sent: Saturday, February 19, 2011 2:01 AM
Subject: R-390 Digest, Vol 82, Issue 18
> Send R-390 mailing list submissions to
> r-390 at mailman.qth.net
>
> To subscribe or unsubscribe via the World Wide Web, visit
> http://mailman.qth.net/mailman/listinfo/r-390
> or, via email, send a message with subject or body 'help' to
> r-390-request at mailman.qth.net
>
> You can reach the person managing the list at
> r-390-owner at mailman.qth.net
>
> When replying, please edit your Subject line so it is more specific
> than "Re: Contents of R-390 digest..."
>
>
> Today's Topics:
>
> 1. AB Ohmite resistors (Ben Loper)
> 2. Re: AB Ohmite resistors (rbethman)
> 3. 3TF7 Ballast Tubes (Ben Loper)
> 4. Re: 3TF7 Ballast Tubes (rbethman)
> 5. Re: 3TF7 Ballast Tubes (Joe Connor)
> 6. Re: 3TF7 Ballast Tubes (Ben Loper)
> 7. Re: 3TF7 Ballast Tubes (rbethman)
> 8. Re: 3TF7 Ballast Tubes (Rick Popovich)
> 9. Re: 3TF7 Ballast Tubes (James A. (Andy) Moorer)
> 10. Re: 3TF7 Ballast Tubes (Tom Frobase)
> 11. Re: 3TF7 Ballast Tubes (Manfred Antar)
>
>
> ----------------------------------------------------------------------
>
> Message: 1
> Date: Fri, 18 Feb 2011 14:43:53 -0600
> From: Ben Loper <brloper at gmail.com>
> Subject: [R-390] AB Ohmite resistors
> To: Collins List <collins at listserve.com>, r-390 at mailman.qth.net
> Message-ID:
> <AANLkTikgae6u9Vt7pmPWDBENNQgjTBr0Lfy3DjgA3YH6 at mail.gmail.com>
> Content-Type: text/plain; charset=UTF-8
>
> While working on my 75A-2 I cam across a source of NOS Allen Bradley and
> Ohmite carbon composition resistors. 1/4 1/2 1 and 2 watts sizes. I was
> putting my list together for what I might need and I wondered if anyone
> needed some. The ones I saw are all unused in packages. Ii haven't had a
> chance to go through all of them, but if there are some frequently used or
> sizes someone needs send me your list. These are the older style and
> again
> completely unused.
>
> --
>
> ?A fire has burned my hut to the ground -- how much better to see the
> moon!"
>
>
> ------------------------------
>
> Message: 2
> Date: Fri, 18 Feb 2011 16:02:51 -0500
> From: rbethman <rbethman at comcast.net>
> Subject: Re: [R-390] AB Ohmite resistors
> To: r-390 at mailman.qth.net
> Message-ID: <4D5EDE7B.1000101 at comcast.net>
> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>
> Ben,
>
> The first suggestion would be to take a "random" sampling to see how the
> values have held up.
>
> I had a bunch like that, even in their original metal box and drawer.
>
> I found that time was NOT their friend!
>
> I've since procured a fair collection of the "newer" metal film type. I
> do random checks, and have yet to find one out of spec.
>
> Since rolling around an R-390A or SP-600 isn't the easiest thing for a
> 60 plus year old, I've taken to the use of the more modern components!
>
> Bob - N0DGN
>
> On 2/18/2011 3:43 PM, Ben Loper wrote:
>> While working on my 75A-2 I cam across a source of NOS Allen Bradley and
>> Ohmite carbon composition resistors. 1/4 1/2 1 and 2 watts sizes. I was
>> putting my list together for what I might need and I wondered if anyone
>> needed some. The ones I saw are all unused in packages. Ii haven't had
>> a
>> chance to go through all of them, but if there are some frequently used
>> or
>> sizes someone needs send me your list. These are the older style and
>> again
>> completely unused.
>>
>
>
>
> ------------------------------
>
> Message: 3
> Date: Fri, 18 Feb 2011 15:35:36 -0600
> From: "Ben Loper" <brloper at gmail.com>
> Subject: [R-390] 3TF7 Ballast Tubes
> To: <r-390 at mailman.qth.net>
> Message-ID: <D960D709E4B34E31BE17C8C521889689 at instrume0a0c4d>
> Content-Type: text/plain; charset="us-ascii"
>
>
>
> I came across some NOS 3TF7 Amperite tubes. Should I make an offer on
> them
> or is the conventional wisdom to replace them with a 12BA6 tube.
>
>
>
> ------------------------------
>
> Message: 4
> Date: Fri, 18 Feb 2011 16:43:28 -0500
> From: rbethman <rbethman at comcast.net>
> Subject: Re: [R-390] 3TF7 Ballast Tubes
> To: Ben Loper <brloper at gmail.com>
> Cc: r-390 at mailman.qth.net
> Message-ID: <4D5EE800.5080001 at comcast.net>
> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>
> Ben,
>
> There is not a "collective" viewpoint regarding these.
>
> My view is *IF* you can get them, and don't have to give up an "arm and
> a Leg" to get them, then I'd stick with the 3TF7s.
>
> The other possible method would be to place a 40 to 50 ohm 10 Watt
> resistor in its place.
>
> I haven't gone the route of using a 12BA6 as of yet.
>
> The resistor came in my '67 EAC, and worked just fine. Currently I have
> one NOS 3TF7 left that is going into my St. J's restoration of the first
> contract Collins.
>
> As is true in just about all instances, YMMV!
>
> Bob - N0DGN
>
> On 2/18/2011 4:35 PM, Ben Loper wrote:
>>
>> I came across some NOS 3TF7 Amperite tubes. Should I make an offer on
>> them
>> or is the conventional wisdom to replace them with a 12BA6 tube.
>
>
>
> ------------------------------
>
> Message: 5
> Date: Fri, 18 Feb 2011 14:24:39 -0800 (PST)
> From: Joe Connor <joeconnor53 at yahoo.com>
> Subject: Re: [R-390] 3TF7 Ballast Tubes
> To: Ben Loper <brloper at gmail.com>, rbethman <rbethman at comcast.net>
> Cc: r-390 at mailman.qth.net
> Message-ID: <863858.10854.qm at web46310.mail.sp1.yahoo.com>
> Content-Type: text/plain; charset=iso-8859-1
>
> For the record, 3TF7s are going for $50 apiece at Fair Radio.
>
> Joe Connor
>
> --- On Fri, 2/18/11, rbethman <rbethman at comcast.net> wrote:
>
>> From: rbethman <rbethman at comcast.net>
>> Subject: Re: [R-390] 3TF7 Ballast Tubes
>> To: "Ben Loper" <brloper at gmail.com>
>> Cc: r-390 at mailman.qth.net
>> Date: Friday, February 18, 2011, 9:43 PM
>> Ben,
>>
>> There is not a "collective" viewpoint regarding these.
>>
>> My view is *IF* you can get them, and don't have to give up
>> an "arm and
>> a Leg" to get them, then I'd stick with the 3TF7s.
>>
>> The other possible method would be to place a 40 to 50 ohm
>> 10 Watt
>> resistor in its place.
>>
>> I haven't gone the route of using a 12BA6 as of yet.
>>
>> The resistor came in my '67 EAC, and worked just
>> fine.? Currently I have
>> one NOS 3TF7 left that is going into my St. J's restoration
>> of the first
>> contract Collins.
>>
>> As is true in just about all instances, YMMV!
>>
>> Bob - N0DGN
>>
>> On 2/18/2011 4:35 PM, Ben Loper wrote:
>> >
>> > I came across some NOS 3TF7 Amperite tubes.?
>> Should I make an offer on them
>> > or is the conventional wisdom to replace them with a
>> 12BA6 tube.
>>
>> ______________________________________________________________
>> 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: 6
> Date: Fri, 18 Feb 2011 16:27:50 -0600
> From: "Ben Loper" <brloper at gmail.com>
> Subject: Re: [R-390] 3TF7 Ballast Tubes
> To: "'Joe Connor'" <joeconnor53 at yahoo.com>, "'rbethman'"
> <rbethman at comcast.net>
> Cc: r-390 at mailman.qth.net
> Message-ID: <BAC8C06DD0B24CA083D8B029694FFE34 at instrume0a0c4d>
> Content-Type: text/plain; charset="iso-8859-1"
>
> I may go ahead and buy these
>
> -----Original Message-----
> From: Joe Connor [mailto:joeconnor53 at yahoo.com]
> Sent: Friday, February 18, 2011 4:25 PM
> To: Ben Loper; rbethman
> Cc: r-390 at mailman.qth.net
> Subject: Re: [R-390] 3TF7 Ballast Tubes
>
>
> For the record, 3TF7s are going for $50 apiece at Fair Radio.
>
> Joe Connor
>
> --- On Fri, 2/18/11, rbethman <rbethman at comcast.net> wrote:
>
>> From: rbethman <rbethman at comcast.net>
>> Subject: Re: [R-390] 3TF7 Ballast Tubes
>> To: "Ben Loper" <brloper at gmail.com>
>> Cc: r-390 at mailman.qth.net
>> Date: Friday, February 18, 2011, 9:43 PM
>> Ben,
>>
>> There is not a "collective" viewpoint regarding these.
>>
>> My view is *IF* you can get them, and don't have to give up an "arm
>> and a Leg" to get them, then I'd stick with the 3TF7s.
>>
>> The other possible method would be to place a 40 to 50 ohm
>> 10 Watt
>> resistor in its place.
>>
>> I haven't gone the route of using a 12BA6 as of yet.
>>
>> The resistor came in my '67 EAC, and worked just
>> fine.? Currently I have
>> one NOS 3TF7 left that is going into my St. J's restoration
>> of the first
>> contract Collins.
>>
>> As is true in just about all instances, YMMV!
>>
>> Bob - N0DGN
>>
>> On 2/18/2011 4:35 PM, Ben Loper wrote:
>> >
>> > I came across some NOS 3TF7 Amperite tubes.
>> Should I make an offer on them
>> > or is the conventional wisdom to replace them with a
>> 12BA6 tube.
>>
>> ______________________________________________________________
>> 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: 7
> Date: Fri, 18 Feb 2011 17:30:33 -0500
> From: rbethman <rbethman at comcast.net>
> Subject: Re: [R-390] 3TF7 Ballast Tubes
> To: r-390 at mailman.qth.net
> Message-ID: <4D5EF309.2010202 at comcast.net>
> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>
> Joe - We all know what they are going for. The price at Fair Radio is
> better than a bunch of others.
>
> Ben - It is like I said, YMMV. The 12BA6 is always and option, as is
> the resistor of ample wattage.
>
> We all decide which "we" want to go.
>
> Bob - N0DGN
>
> On 2/18/2011 5:27 PM, Ben Loper wrote:
>> I may go ahead and buy these
>>
>> -----Original Message-----
>> From: Joe Connor [mailto:joeconnor53 at yahoo.com]
>> Sent: Friday, February 18, 2011 4:25 PM
>> To: Ben Loper; rbethman
>> Cc: r-390 at mailman.qth.net
>> Subject: Re: [R-390] 3TF7 Ballast Tubes
>>
>>
>> For the record, 3TF7s are going for $50 apiece at Fair Radio.
>>
>> Joe Connor
>
>
>
> ------------------------------
>
> Message: 8
> Date: Fri, 18 Feb 2011 15:58:03 -0800
> From: "Rick Popovich" <RickP at uei.csus.edu>
> Subject: Re: [R-390] 3TF7 Ballast Tubes
> To: <r-390 at mailman.qth.net>
> Message-ID:
> <189623A7E3D4FA4C90268D050814EFDE01352455 at ueimail.uei.csus.edu>
> Content-Type: text/plain; charset="us-ascii"
>
> This is why I joined this list - I'm always learning something new.
>
> Which leads to my question; is the 12BA6 a DIRECT substitute for the
> 3TF7 ? - meaning no wiring changes are needed under the tube socket ?
>
> I just had a 3TF7 go bad on my R-390 and don't have a spare. I DO have
> plenty of 12BA6's. I would prefer to go that route as opposed to using
> the resistor if no other mods are needed.
>
> Tnx again to all.
>
> Rick - WB6RMQ
>
> Collins R-391
> Motorola R-390
> Capehart R-390A
>
> -----Original Message-----
> From: r-390-bounces at mailman.qth.net
> [mailto:r-390-bounces at mailman.qth.net] On Behalf Of rbethman
> Sent: Friday, February 18, 2011 2:31 PM
> To: r-390 at mailman.qth.net
> Subject: Re: [R-390] 3TF7 Ballast Tubes
>
> Joe - We all know what they are going for. The price at Fair Radio is
> better than a bunch of others.
>
> Ben - It is like I said, YMMV. The 12BA6 is always and option, as is
> the resistor of ample wattage.
>
> We all decide which "we" want to go.
>
> Bob - N0DGN
>
> On 2/18/2011 5:27 PM, Ben Loper wrote:
>> I may go ahead and buy these
>>
>> -----Original Message-----
>> From: Joe Connor [mailto:joeconnor53 at yahoo.com]
>> Sent: Friday, February 18, 2011 4:25 PM
>> To: Ben Loper; rbethman
>> Cc: r-390 at mailman.qth.net
>> Subject: Re: [R-390] 3TF7 Ballast Tubes
>>
>>
>> For the record, 3TF7s are going for $50 apiece at Fair Radio.
>>
>> Joe Connor
>
> ______________________________________________________________
> 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: 9
> Date: Fri, 18 Feb 2011 19:04:03 -0500
> From: "James A. (Andy) Moorer" <jamminpower at earthlink.net>
> Subject: Re: [R-390] 3TF7 Ballast Tubes
> To: r-390 at mailman.qth.net
> Message-ID: <4D5F08F3.9000806 at earthlink.net>
> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>
> Hmm. In the spirit of the re-stuffed capacitor cans, maybe we could
> find some similar-looking dead ballast tubes, carefully hollow them out
> and put a nice, shiny resistor in it & seal it back up. I believe they
> use soft glass for tubes, so a good jeweler's torch should do the trick.
>
> -A
>
> --
> James A. (Andy) Moorer
> www.jamminpower.com
>
>
>
> On 2/18/2011 5:30 PM, rbethman wrote:
>> Joe - We all know what they are going for. The price at Fair Radio is
>> better than a bunch of others.
>>
>> Ben - It is like I said, YMMV. The 12BA6 is always and option, as is
>> the resistor of ample wattage.
>>
>> We all decide which "we" want to go.
>>
>> Bob - N0DGN
>>
>> On 2/18/2011 5:27 PM, Ben Loper wrote:
>>> I may go ahead and buy these
>>>
>>> -----Original Message-----
>>> From: Joe Connor [mailto:joeconnor53 at yahoo.com]
>>> Sent: Friday, February 18, 2011 4:25 PM
>>> To: Ben Loper; rbethman
>>> Cc: r-390 at mailman.qth.net
>>> Subject: Re: [R-390] 3TF7 Ballast Tubes
>>>
>>>
>>> For the record, 3TF7s are going for $50 apiece at Fair Radio.
>>>
>
>
>
> ------------------------------
>
> Message: 10
> Date: Fri, 18 Feb 2011 18:42:42 -0600
> From: Tom Frobase <tfrobase at gmail.com>
> Subject: Re: [R-390] 3TF7 Ballast Tubes
> To: r-390 at mailman.qth.net
> Message-ID: <4D5F1202.8080506 at gmail.com>
> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>
>
> You replace the 2 tubes that are in series with the Ballast V505 and
> V701 with 12BA6's and put a jumper between pins 2 and 7 on the ballast
> socket. tom, N3LLL
>
>
> On 2/18/2011 5:58 PM, Rick Popovich wrote:
>> This is why I joined this list - I'm always learning something new.
>>
>> Which leads to my question; is the 12BA6 a DIRECT substitute for the
>> 3TF7 ? - meaning no wiring changes are needed under the tube socket ?
>
>
>
> ------------------------------
>
> Message: 11
> Date: Fri, 18 Feb 2011 17:00:08 -0800
> From: Manfred Antar <mantar at pacbell.net>
> Subject: Re: [R-390] 3TF7 Ballast Tubes
> To: Tom Frobase <tfrobase at gmail.com>, r-390 at mailman.qth.net
> Message-ID: <201102190100.p1J1097r002398 at nlpi129.prodigy.net>
> Content-Type: text/plain; charset="us-ascii"
>
> At 04:42 PM 2/18/2011, Tom Frobase wrote:
>
>>You replace the 2 tubes that are in series with the Ballast V505 and
>>V701 with 12BA6's and put a jumper between pins 2 and 7 on the ballast
>>socket. tom, N3LLL
>>
>>
>>On 2/18/2011 5:58 PM, Rick Popovich wrote:
>>> This is why I joined this list - I'm always learning something new.
>>>
>>> Which leads to my question; is the 12BA6 a DIRECT substitute for the
>>> 3TF7 ? - meaning no wiring changes are needed under the tube socket ?
>
> There is a guy in Germany that makes a solid state replacement that fits
> in the 3TF7 socket
> I use one in one of my R390A's and have ordered another one for the other
> R-390A
> They work great
> The cost is $72.50 plus postage from germany.
> He also builds new filer caps for the AF deck that are real nice
>
> Here is the web address:
>
> http://www.sigma-tec.eu/cartview.php?id=16
>
>
>
> ==================================
> || null at pozo.com ||
> || Ph. (415) 681-6235 ||
> ==================================
>
>
>
More information about the R-390
mailing list