Date   

Re: 7A12 attenuator board clone

Jim Ford
 

Thanks, Roy.  I hadn't thought about how the wetting process works.  I just wanted to point out that if a person is used to tin/lead solder, he or she will go WTF when first using indium solder.  I should have been clearer.JimSent from my Verizon, Samsung Galaxy smartphone

-------- Original message --------From: Roy Thistle <roy.thistle@mail.utoronto.ca> Date: 11/15/20 11:38 AM (GMT-08:00) To: TekScopes@groups.io Subject: Re: [TekScopes] 7A12 attenuator board clone On Sat, Nov 14, 2020 at 07:30 PM, Jim Ford wrote:>> unless a lot has changed in the last few decades, indium-based solder really> sucks!>Well... yes... technology is apt to change (for the better?), with 2 decades past.All of us are familiar with the way that tin/lead solder spreads due to its wetting. But, I.M.O. it's a mistake to project this onto other solder technologies. Spreading is a competition between the forces of surface tension (trying to ball the solder up)... and wetting (trying to spread the solder out)... and to an extent... the solder dissolving into the surface forming an inter-metallic.Because a solder does not behave like the tin/lead one we are used to, does not mean there is not a good inter-metallic formed.


Re: 7L5 Res shaft encoder

Nenad Filipovic
 

On Fri, Nov 13, 2020 at 8:30 PM Jean-Paul <jonpaul@ix.netcom.com> wrote:
FREQ knob has several defective positions, 1k 2k 5kHz : These
intermittently fault to 100k, 200k and 500k respectively.

I have a 7L5 with a similar problem and it's driving me nuts. Restoration
of front panel PCB sockets made no difference, so it all points to the knob
(switch) being the problem. I found a few old posts on the group dealing
with this issue but (someone please correct me if I missed it) no one yet
dared disassemble the knob. IIRC I read somewhere else that it may crumble
into zillion little pieces which are a nightmare to put back properly.

I've seen a fair number of 7L5's on eBay with broken knobs; would be great
if someone from our group had such an unusable one and would be willing to
dissect it and photograph the process. I admit I'm a chicken to disassemble
mine and possibly end up with a dead 7L5 (far from Tek homeland in Eastern
Europe, where I live).

Best regards,
Nenad


Re: 7A12 attenuator board clone

Roy Thistle
 

On Sat, Nov 14, 2020 at 07:30 PM, Jim Ford wrote:


unless a lot has changed in the last few decades, indium-based solder really
sucks!
Well... yes... technology is apt to change (for the better?), with 2 decades past.
All of us are familiar with the way that tin/lead solder spreads due to its wetting.
But, I.M.O. it's a mistake to project this onto other solder technologies.
Spreading is a competition between the forces of surface tension (trying to ball the solder up)... and wetting (trying to spread the solder out)... and to an extent... the solder dissolving into the surface forming an inter-metallic.
Because a solder does not behave like the tin/lead one we are used to, does not mean there is not a good inter-metallic formed.


Re: Special Offer from Peter Keller to TekScopes Members: The Cathode Ray Tube, Technology, History, and Applications"

Kurt Rosenfeld
 

In 2018 I got permission from Mr. Keller to extract data from one of his articles and use it here:
http://w140.com/tekwiki/wiki/Cathode-ray_tube#Classic_Tektronix_CRTs_.28info_provided_by_Peter_Keller.29
There was no discussion of any other documents or permissions.


Re: Special Offer from Peter Keller to TekScopes Members: The Cathode Ray Tube, Technology, History, and Applications"

 

In that case I definitely won't buy the book.
W7pF

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of Leon Robinson
Sent: Sunday, November 15, 2020 9:44 AM
To: TekScopes@groups.io
Subject: Re: [TekScopes] Special Offer from Peter Keller to TekScopes Members: The Cathode Ray Tube, Technology, History, and Applications"

Dennis,
That won't even get close. When my wife and I got married in 1967 $750 covered round trip air fare from Miami and a weeks stay at the Sheraton British Colonial in Nassau. Just looked up inflation rate since then, $6850 USD


Leon Robinson K5JLR

-------- Original message --------
From: Dennis Tillman W7pF <dennis@ridesoft.com>
Date: 11/14/2020 10:23 PM (GMT-06:00)
To: TekScopes@groups.io
Subject: Re: [TekScopes] Special Offer from Peter Keller to TekScopes Members: The Cathode Ray Tube, Technology, History, and Applications"

OK, its official, we have reached the 20 book price of $30 + shipping.

Meanwhile, at this very moment on eBay (item number:123833837045), Peter's
book is for sale for ONLY $650. Unless that price includes an all-expenses
paid trip to the Bahamas to pick up the book I don't think any of us are
likely to buy it.

Dennis Tillman W7pF

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of Dennis
Tillman W7pF
Sent: Saturday, November 14, 2020 4:52 PM
To: TekScopes@groups.io
Cc: 'Kurt Rosenfeld' <kurt.harlem@gmail.com>
Subject: Re: [TekScopes] Special Offer from Peter Keller to TekScopes
Members: The Cathode Ray Tube, Technology, History, and Applications"

We have reached the first break point. I now have 10 firm orders for Peter's
book. If there are another 10 orders in the next few days (which I think is
highly likely) the price will drop to $30 plus shipping.
I think a week is a reasonable amount of time for me to wait so everyone has
had a chance to respond to Peter's offer. If anyone has a better idea please
let me know.

This is what Siggi just told me when he placed his order a minute ago:
<snip>
PS: I've started reading the book already from the online copy, and it's
awesome. It's just knocking over every question I've ever had about CRTs,
one by one.

Who knows what happens to the price after 20 copies? I will be happy to ask
Peter if that happens.
Dennis Tillman W7pF
_____________________________________________
From: Dennis Tillman W7pF [mailto:dennis@ridesoft.com]
Sent: Saturday, November 14, 2020 1:58 PM
To: TekScopes@groups.io Notification (TekScopes@groups.io)
<TekScopes@groups.io>
Cc: 'Kurt Rosenfeld' <kurt.harlem@gmail.com>
Subject: Special Offer from Peter Keller to TekScopes Members: The Cathode
Ray Tube, Technology, History, and Applications"


In 2017 when I bought my copy of Peter Keller's definitive book on the CRT I
paid $70 for it.

1) PETER WAS VERY CLEAR: HE HAS NOT GIVEN ANYONE PERMISSION TO SCAN HIS BOOK
OR TURN IT INTO AN ELECTRONIC, DOWNLOADABLE, FILE (but he has made it
possible to buy it at a huge discount)
2) The 6-part, 36-page article that Bill Perkins scanned on the Tektronix
CRTs was originally published by the Tube Collectors Association which has
since disbanded. As far as Peter is concerned we may post it to our website.
It will then be accessible to more researchers and collectors there.
3) I (Dennis Tillman) also think this article should be posted to TekWiki.

AND NOW FOR THE VERY GOOD NEWS:
Peter's book is still available in hard cover and he has copies of to sell.
Because of recent interest in it from more than five members of TekScopes I
went out on a limb and asked if a discount would be available if I could
guarantee him an order of at least 10 copies of his book provided I did all
the work of collecting the funds and mailing the copies to our members. In
his reply (BELOW) he offered our members a huge discount. The cost would be
$40 + shipping if we order 10 copies or $30 + shipping for an order of 20
copies of his book. If there are 20 orders that will mean your copy will
cost less than half of what I paid for my copy. Also, I believe I can even
get him to autograph each copy.

If there are enough orders I will collect the funds and ship each order to
our members. In the meantime I will find out the most economical way to ship
these.

If you definitely want a copy of Peter's book contact me OFF-LIST at dennis
at ridesoft dot com and include your address. Once I know what the postage
will cost and how many orders we have I will know what the final price will
be for each of you.

Dennis Tillman W7pF

From: Peter Keller
Sent: Friday, November 13, 2020 9:25 PM
To: dennis@ridesoft.com <mailto:dennis@ridesoft.com>
Subject: RE: Inquiries about your book

Hi Dennis,
I have been selling them at $69.50 plus $6.00 shipping. For ten all shipped
to one address at one time I would be willing to sell them at $39.50 each
plus actual shipping cost. Ten copies would weigh about 25-30 pounds I
believe. Twenty copies would be $29.50 each plus shipping.

Peter












--
Dennis Tillman W7pF
TekScopes Moderator













--
Dennis Tillman W7pF
TekScopes Moderator


Re: Special Offer from Peter Keller to TekScopes Members: The Cathode Ray Tube, Technology, History, and Applications"

Leon Robinson
 

Dennis, 
That won't even get close.  When my wife and I got married in 1967 $750 covered round trip air fare from Miami and a weeks stay at the Sheraton British Colonial in Nassau.  Just looked up inflation rate since then,  $6850 USD


Leon Robinson  K5JLR

-------- Original message --------
From: Dennis Tillman W7pF <dennis@ridesoft.com>
Date: 11/14/2020 10:23 PM (GMT-06:00)
To: TekScopes@groups.io
Subject: Re: [TekScopes] Special Offer from Peter Keller to TekScopes Members: The Cathode Ray Tube, Technology, History, and Applications"

OK, its official, we have reached the 20 book price of $30 + shipping.

Meanwhile, at this very moment on eBay (item number:123833837045), Peter's
book is for sale for ONLY $650. Unless that price includes an all-expenses
paid trip to the Bahamas to pick up the book I don't think any of us are
likely to buy it.

Dennis Tillman W7pF

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of Dennis
Tillman W7pF
Sent: Saturday, November 14, 2020 4:52 PM
To: TekScopes@groups.io
Cc: 'Kurt Rosenfeld' <kurt.harlem@gmail.com>
Subject: Re: [TekScopes] Special Offer from Peter Keller to TekScopes
Members: The Cathode Ray Tube, Technology, History, and Applications"

We have reached the first break point. I now have 10 firm orders for Peter's
book. If there are another 10 orders in the next few days (which I think is
highly likely) the price will drop to $30 plus shipping.
I think a week is a reasonable amount of time for me to wait so everyone has
had a chance to respond to Peter's offer. If anyone has a better idea please
let me know.

This is what Siggi just told me when he placed his order a minute ago:
<snip>
PS: I've started reading the book already from the online copy, and it's
awesome. It's just knocking over every question I've ever had about CRTs,
one by one.

Who knows what happens to the price after 20 copies? I will be happy to ask
Peter if that happens.
Dennis Tillman W7pF
_____________________________________________
From: Dennis Tillman W7pF [mailto:dennis@ridesoft.com]
Sent: Saturday, November 14, 2020 1:58 PM
To: TekScopes@groups.io Notification (TekScopes@groups.io)
<TekScopes@groups.io>
Cc: 'Kurt Rosenfeld' <kurt.harlem@gmail.com>
Subject: Special Offer from Peter Keller to TekScopes Members: The Cathode
Ray Tube, Technology, History, and Applications"


In 2017 when I bought my copy of Peter Keller's definitive book on the CRT I
paid $70 for it.

1) PETER WAS VERY CLEAR: HE HAS NOT GIVEN ANYONE PERMISSION TO SCAN HIS BOOK
OR TURN IT INTO AN ELECTRONIC, DOWNLOADABLE, FILE (but he has made it
possible to buy it at a huge discount)
2) The 6-part, 36-page article that Bill Perkins scanned on the Tektronix
CRTs was originally published by the Tube Collectors Association which has
since disbanded. As far as Peter is concerned we may post it to our website.
It will then be accessible to more researchers and collectors there.
3) I (Dennis Tillman) also think this article should be posted to TekWiki.

AND NOW FOR THE VERY GOOD NEWS:
Peter's book is still available in hard cover and he has copies of to sell.
Because of recent interest in it from more than five members of TekScopes I
went out on a limb and asked if a discount would be available if I could
guarantee him an order of at least 10 copies of his book provided I did all
the work of collecting the funds and mailing the copies to our members. In
his reply (BELOW) he offered our members a huge discount. The cost would be
$40 + shipping if we order 10 copies or $30 + shipping for an order of 20
copies of his book. If there are 20 orders that will mean your copy will
cost less than half of what I paid for my copy. Also, I believe I can even
get him to autograph each copy.

If there are enough orders I will collect the funds and ship each order to
our members. In the meantime I will find out the most economical way to ship
these.

If you definitely want a copy of Peter's book contact me OFF-LIST at dennis
at ridesoft dot com and include your address. Once I know what the postage
will cost and how many orders we have I will know what the final price will
be for each of you.

Dennis Tillman W7pF

From: Peter Keller
Sent: Friday, November 13, 2020 9:25 PM
To: dennis@ridesoft.com <mailto:dennis@ridesoft.com>
Subject: RE: Inquiries about your book

Hi Dennis,
I have been selling them at $69.50 plus $6.00 shipping. For ten all shipped
to one address at one time I would be willing to sell them at $39.50 each
plus actual shipping cost. Ten copies would weigh about 25-30 pounds I
believe.  Twenty copies would be $29.50 each plus shipping.

Peter












--
Dennis Tillman W7pF
TekScopes Moderator


Re: Peter Keller CRT Articles and Book. WAS: Reworked Tek' Lit

 

Hi Raymond,
I did get it.
I was surprised to see you are in the Netherlands.
Marian and I have such wonderful memories of our vacation there many years ago.
Dennis

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of Raymond Domp Frank
Sent: Sunday, November 15, 2020 8:13 AM
To: TekScopes@groups.io
Subject: Re: [TekScopes] Peter Keller CRT Articles and Book. WAS: Reworked Tek' Lit

Attn. Dennis Tillman,

I sent you a PM earlier today. Because of recent problems with email messaging I'd appreciate your confirmation that you received my message.

Raymond







--
Dennis Tillman W7pF
TekScopes Moderator


Re: Peter Keller CRT Articles and Book. WAS: Reworked Tek' Lit

 

Attn. Dennis Tillman,

I sent you a PM earlier today. Because of recent problems with email messaging I'd appreciate your confirmation that you received my message.

Raymond


Re: Another A5 board repair attemp - help needed

Rogerio O
 

Thank you Siggi.
I have already order a DAC312 along with my parts order.
They are schedule to arrive at Tuesday afternoon.
However, I guess I have a "donor" A5 board that was severely damaged by corrosion somewhere in my junk.
I will check if I can find it.
If I don't I will have to wait for the parts to arrive.
Roger


Re: 7L5 Res shaft encoder

Dan G
 

On Sat, Nov 14, 2020 at 04:42 AM, Jean-Paul wrote:

The original TEK service manual reveals the knobs are just switches, circular
PCB and wipers. No shaft encoder!
Pressing the knob in/out or pushing the front panel can change it 5k><500K.
Probably a single contact on the x1 x100 switch.
I washed with 99% iso alcohol, no change. Suspect oxidized connector on shaft
encoder to front panel PCB.
Interesting. I've found the article that I had vaguely remembered at first:

"A 5MHz digitally controlled spectrum analyzer" published in TekScope Volume 7
Number 3. Towards the end of the article, it describes the optical encoder innovation,
and states that it is used for TIME/DIV and FREQUENY SPAN/DIV controls.

Looking at the Front Panel <2> schematic in my service manual, only the resolution
selector seems to be mechanical. Is it possible that Tek had at some point switched
to an all-mechanical solution, and your unit happens to be one of those?


dan


Re: Special Offer from Peter Keller to TekScopes Members: The Cathode Ray Tube, Technology, History, and Applications"

 

Hi Dave,
I believe I first discovered Peter Keller when I came across some issues of the Tube Collectors Journal at a ham swap meet. I had some, but not all, of the series. I still have them somewhere but there is no hope of finding them at the moment in my mess.

I was thinking of coming down to Beaverton. It would be nice to see Peter again but it seems like it is getting too dangerous to travel once again.

If I am not mistaken Kurt Rosenfeld spoke to Peter in 2017 when I bought my copy of Peter's CRT book. I do not know what came of that conversation. Maybe Kurt can fill you in

Dennis

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of Dave Brown
Sent: Saturday, November 14, 2020 8:08 PM
To: TekScopes@groups.io
Subject: Re: [TekScopes] Special Offer from Peter Keller to TekScopes Members: The Cathode Ray Tube, Technology, History, and Applications"

The vintageTEK museum has the 6-part 36-page article that Bill Perkins scanned on the Tektronix CRTs that was originally published by the Tube Collectors Association. It is hosted at https://vintagetek.org/tektronix-crt-history/

Dave







--
Dennis Tillman W7pF
TekScopes Moderator


Re: Special Offer from Peter Keller to TekScopes Members: The Cathode Ray Tube, Technology, History, and Applications"

 

OK, its official, we have reached the 20 book price of $30 + shipping.

Meanwhile, at this very moment on eBay (item number:123833837045), Peter's
book is for sale for ONLY $650. Unless that price includes an all-expenses
paid trip to the Bahamas to pick up the book I don't think any of us are
likely to buy it.

Dennis Tillman W7pF

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of Dennis
Tillman W7pF
Sent: Saturday, November 14, 2020 4:52 PM
To: TekScopes@groups.io
Cc: 'Kurt Rosenfeld' <kurt.harlem@gmail.com>
Subject: Re: [TekScopes] Special Offer from Peter Keller to TekScopes
Members: The Cathode Ray Tube, Technology, History, and Applications"

We have reached the first break point. I now have 10 firm orders for Peter's
book. If there are another 10 orders in the next few days (which I think is
highly likely) the price will drop to $30 plus shipping.
I think a week is a reasonable amount of time for me to wait so everyone has
had a chance to respond to Peter's offer. If anyone has a better idea please
let me know.

This is what Siggi just told me when he placed his order a minute ago:
<snip>
PS: I've started reading the book already from the online copy, and it's
awesome. It's just knocking over every question I've ever had about CRTs,
one by one.

Who knows what happens to the price after 20 copies? I will be happy to ask
Peter if that happens.
Dennis Tillman W7pF
_____________________________________________
From: Dennis Tillman W7pF [mailto:dennis@ridesoft.com]
Sent: Saturday, November 14, 2020 1:58 PM
To: TekScopes@groups.io Notification (TekScopes@groups.io)
<TekScopes@groups.io>
Cc: 'Kurt Rosenfeld' <kurt.harlem@gmail.com>
Subject: Special Offer from Peter Keller to TekScopes Members: The Cathode
Ray Tube, Technology, History, and Applications"


In 2017 when I bought my copy of Peter Keller's definitive book on the CRT I
paid $70 for it.

1) PETER WAS VERY CLEAR: HE HAS NOT GIVEN ANYONE PERMISSION TO SCAN HIS BOOK
OR TURN IT INTO AN ELECTRONIC, DOWNLOADABLE, FILE (but he has made it
possible to buy it at a huge discount)
2) The 6-part, 36-page article that Bill Perkins scanned on the Tektronix
CRTs was originally published by the Tube Collectors Association which has
since disbanded. As far as Peter is concerned we may post it to our website.
It will then be accessible to more researchers and collectors there.
3) I (Dennis Tillman) also think this article should be posted to TekWiki.

AND NOW FOR THE VERY GOOD NEWS:
Peter's book is still available in hard cover and he has copies of to sell.
Because of recent interest in it from more than five members of TekScopes I
went out on a limb and asked if a discount would be available if I could
guarantee him an order of at least 10 copies of his book provided I did all
the work of collecting the funds and mailing the copies to our members. In
his reply (BELOW) he offered our members a huge discount. The cost would be
$40 + shipping if we order 10 copies or $30 + shipping for an order of 20
copies of his book. If there are 20 orders that will mean your copy will
cost less than half of what I paid for my copy. Also, I believe I can even
get him to autograph each copy.

If there are enough orders I will collect the funds and ship each order to
our members. In the meantime I will find out the most economical way to ship
these.

If you definitely want a copy of Peter's book contact me OFF-LIST at dennis
at ridesoft dot com and include your address. Once I know what the postage
will cost and how many orders we have I will know what the final price will
be for each of you.

Dennis Tillman W7pF

From: Peter Keller
Sent: Friday, November 13, 2020 9:25 PM
To: dennis@ridesoft.com <mailto:dennis@ridesoft.com>
Subject: RE: Inquiries about your book

Hi Dennis,
I have been selling them at $69.50 plus $6.00 shipping. For ten all shipped
to one address at one time I would be willing to sell them at $39.50 each
plus actual shipping cost. Ten copies would weigh about 25-30 pounds I
believe. Twenty copies would be $29.50 each plus shipping.

Peter












--
Dennis Tillman W7pF
TekScopes Moderator


Re: Peter Keller CRT Articles and Book. WAS: Reworked Tek' Lit

Bill Perkins <sales@...>
 

Want a laugh? Check this out.
https://www.ebay.com/itm/The-Cathode-Ray-Tube-Technology-History-and-Applications-by-Peter-A-Keller/123833837045?epid=817090&hash=item1cd51265f5:g:gKkAAOSw01pdKRvs
I wrote guy as follows:

Dude:
Over on the TekScopes@groups.io list we're arranging a group buy of -exactly- this book, new from the author and autographed.

With about 10 guys committed the price is $US40.00 and once we reach 20 copies it'll drop to $US30.00, plus postage of course.

Sorry to buzz-kill your gig here but we all had quite a laugh.

Bill


Re: Special Offer from Peter Keller to TekScopes Members: The Cathode Ray Tube, Technology, History, and Applications"

Dave Brown
 

The vintageTEK museum has the 6-part 36-page article that Bill Perkins scanned on the Tektronix
CRTs that was originally published by the Tube Collectors Association. It is hosted at https://vintagetek.org/tektronix-crt-history/

Dave


Re: Peter Keller CRT Articles and Book. WAS: Reworked Tek' Lit

John Williams
 


Re: 7A12 attenuator board clone

Tom Lee
 

I suspected as much. I only use indium as a dopant.

--Tom

--
Prof. Thomas H. Lee
Allen Ctr., Rm. 205
350 Jane Stanford Way
Stanford University
Stanford, CA 94305-4070
http://www-smirc.stanford.edu

On 11/14/2020 19:30, Jim Ford wrote:
Well, unless a lot has changed in the last few decades, indium-based solder really sucks!  Indium Corp says it doesn't wet as well as tin/lead solder.  No, it doesn't wet at all!  The wire form just blobs up on the end of the soldering iron.  It might work better as a paste with some mildly activated or activated rosin flux mixed in and reflowed in an oven, but it's really difficult to use for hand soldering.  Not user-friendly!

Jim Ford

------ Original Message ------
From: "Roy Thistle" <roy.thistle@mail.utoronto.ca>
To: TekScopes@groups.io
Sent: 11/14/2020 6:34:40 PM
Subject: Re: [TekScopes] 7A12 attenuator board clone

On Fri, Nov 13, 2020 at 01:53 PM, Tom Lee wrote:


 PPO’s melting point is not that much higher than butter’s...you do have to exercise care in soldering. If you apply any forces — lateral or vertical — during soldering, things will move around.
did you try an In based solder?








Re: 7A12 attenuator board clone

Jim Ford
 

Well, unless a lot has changed in the last few decades, indium-based solder really sucks! Indium Corp says it doesn't wet as well as tin/lead solder. No, it doesn't wet at all! The wire form just blobs up on the end of the soldering iron. It might work better as a paste with some mildly activated or activated rosin flux mixed in and reflowed in an oven, but it's really difficult to use for hand soldering. Not user-friendly!

Jim Ford

------ Original Message ------
From: "Roy Thistle" <roy.thistle@mail.utoronto.ca>
To: TekScopes@groups.io
Sent: 11/14/2020 6:34:40 PM
Subject: Re: [TekScopes] 7A12 attenuator board clone

On Fri, Nov 13, 2020 at 01:53 PM, Tom Lee wrote:


PPO’s melting point is not that much higher than butter’s...you do have to exercise care in soldering. If you apply any forces — lateral or vertical — during soldering, things will move around.
did you try an In based solder?





Re: 7A12 attenuator board clone

Tom Lee
 

LOL!

--Cheers,
Tom

--
Prof. Thomas H. Lee
Allen Ctr., Rm. 205
350 Jane Stanford Way
Stanford University
Stanford, CA 94305-4070
http://www-smirc.stanford.edu

On 11/14/2020 19:16, Jack Reynolds wrote:
Tom,

I am assuming this is technical advice of a sort as opposed to lifestyle!

Jack

On 11/14/2020 10:03 PM, Tom Lee wrote:
Being gentle and quick suffices.

--Tom



Re: 7A12 attenuator board clone

Jack Reynolds
 

Tom,

I am assuming this is technical advice of a sort as opposed to lifestyle!

Jack

On 11/14/2020 10:03 PM, Tom Lee wrote:
Being gentle and quick suffices.

--Tom


Re: 7A12 attenuator board clone

Tom Lee
 

Being gentle and quick suffices.

--Tom

--
Prof. Thomas H. Lee
Allen Ctr., Rm. 205
350 Jane Stanford Way
Stanford University
Stanford, CA 94305-4070
http://www-smirc.stanford.edu

On 11/14/2020 18:34, Roy Thistle wrote:
On Fri, Nov 13, 2020 at 01:53 PM, Tom Lee wrote:

PPO’s melting point is not that much higher than butter’s...you do have to exercise care in soldering. If you apply any forces — lateral or vertical — during soldering, things will move around.
did you try an In based solder?



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