Re: [Drakelist] AC3 vs AC4

[Ron]

Larry,
I see my dyslexia is setting in again.  Sorry about that.
73,
Ron WD8SBB

--- On Sat, 3/10/12, kc9...@aol.com  wrote:

From: kc9...@aol.com 
Subject: Re: [Drakelist] AC3 vs AC4
To: wd8...@yahoo.com, drakelist@zerobeat.net, k...@verizon.net
Date: Saturday, March 10, 2012, 3:24 PM

Ron,
Larry has a AC-4 so he's good to go on the AC4-R from Mike.
73,
Lee


260-403-6936 Cell


-Original Message-
From: Ron 
To: drakelist ; K3VX 
Sent: Sat, Mar 10, 2012 3:10 pm
Subject: Re: [Drakelist] AC3 vs AC4




Larry,
Although I prefer the Heathkitshop board, for the AC3, I would go with the 
Hayseed Hamfest caps for the following reasons.

First, the AC3 has a test point on that the AC4 does not and the Heathkitshop 
board does not account for.  That test point is the absolute easiest way to set 
the finals bias current on a rig.  I modified my Heathkit shop board to 
accommodate this test point with my AC4. Second is that the AC3 does not have a 
cover.  That means that with the Heathkit shop board, you have exposed voltages 
on the top of the chassis.

I personally prefer the Heathkitshop board, but it was designed for the AC4.  
It is your call, but if you do use the board on an AC3, please make some type 
of cover, or make other accommodations for safety.  Death is permanent.

73,
Ron WD8SBB

--- On Sat, 3/10/12, K3VX  wrote:


From: K3VX 
Subject: [Drakelist] AC3 vs AC4
To: drakelist@zerobeat.net
Date: Saturday, March 10, 2012, 10:40 AM


I have an AC-4 but the documentation that came with  the T4-X is for the AC3.

All the electrolytic caps have to be replaced as well as some other parts.

Differences between the models?? Also sources for the caps?

Thanks for any help you can give.

Larry K3VX, VP2MVX, 8P9VX


-Inline Attachment Follows-


___
Drakelist mailing list
Drakelist@zerobeat.net
http://mailman.zerobeat.net/mailman/listinfo/drakelist





___
Drakelist mailing list
Drakelist@zerobeat.net
http://mailman.zerobeat.net/mailman/listinfo/drakelist

___
Drakelist mailing list
Drakelist@zerobeat.net
http://mailman.zerobeat.net/mailman/listinfo/drakelist

Re: [Drakelist] AC3 vs AC4

[jvodenik]

On 3/10/2012 1:19 PM, Mark Pilant wrote:

Hi Larry.

As Garey said you can to an original style rebuild using the Hayseed
Hamfest parts.  Here is a page I put together showing my AC-4 rebuild:

http://www.n1vqw.net/ac4rebuild/



Does anyone have an extra AC-4 supply they don't need?  I have sight 
issues and have lost depth preception. That said, my efforts on upgrade 
look pretty crappy, that said, I burned of wiring around the 
connections. Figure I could get another AC-4 and try again with a bit 
smaller wire size.


TNX in advance,
73 de WB9AUJ
jvode...@verizon.net
jvode...@bbg.gov



As for the AC-4 documentation, it is available in a number of places
on the web.  Usually as part of the TR-4 (and probably other T-4..
rigs.)

73

- Mark  N1VQW

___
Drakelist mailing list
Drakelist@zerobeat.net
http://mailman.zerobeat.net/mailman/listinfo/drakelist

___
No infections found in this incoming message
Scanned by iolo System Shield®
http://www.iolo.com






___
Drakelist mailing list
Drakelist@zerobeat.net
http://mailman.zerobeat.net/mailman/listinfo/drakelist

Re: [Drakelist] AC3 vs AC4

[kc9cdt]

Ron,
Larry has a AC-4 so he's good to go on the AC4-R from Mike.
73,
Lee


260-403-6936 Cell


-Original Message-
From: Ron 
To: drakelist ; K3VX 
Sent: Sat, Mar 10, 2012 3:10 pm
Subject: Re: [Drakelist] AC3 vs AC4




Larry,
Although I prefer the Heathkitshop board, for the AC3, I would go with 
the Hayseed Hamfest caps for the following reasons.


First, the AC3 has a test point on that the AC4 does not and the 
Heathkitshop board does not account for.  That test point is the 
absolute easiest way to set the finals bias current on a rig.  I 
modified my Heathkit shop board to accommodate this test point with my 
AC4. Second is that the AC3 does not have a cover.  That means that 
with the Heathkit shop board, you have exposed voltages on the top of 
the chassis.


I personally prefer the Heathkitshop board, but it was designed for the 
AC4.  It is your call, but if you do use the board on an AC3, please 
make some type of cover, or make other accommodations for safety.  
Death is permanent.


73,
Ron WD8SBB

--- On Sat, 3/10/12, K3VX  wrote:


From: K3VX 
Subject: [Drakelist] AC3 vs AC4
To: drakelist@zerobeat.net
Date: Saturday, March 10, 2012, 10:40 AM


I have an AC-4 but the documentation that came with  the T4-X is for 
the AC3.


All the electrolytic caps have to be replaced as well as some other 
parts.


Differences between the models?? Also sources for the caps?

Thanks for any help you can give.

Larry K3VX, VP2MVX, 8P9VX


-Inline Attachment Follows-


___
Drakelist mailing list
Drakelist@zerobeat.net
http://mailman.zerobeat.net/mailman/listinfo/drakelist





___
Drakelist mailing list
Drakelist@zerobeat.net
http://mailman.zerobeat.net/mailman/listinfo/drakelist


___
Drakelist mailing list
Drakelist@zerobeat.net
http://mailman.zerobeat.net/mailman/listinfo/drakelist

Re: [Drakelist] AC3 vs AC4

[Ron]

Larry,
Although I prefer the Heathkitshop board, for the AC3, I would go with the 
Hayseed Hamfest caps for the following reasons.

First, the AC3 has a test point on that the AC4 does not and the Heathkitshop 
board does not account for.  That test point is the absolute easiest way to set 
the finals bias current on a rig.  I modified my Heathkit shop board to 
accommodate this test point with my AC4. Second is that the AC3 does not have a 
cover.  That means that with the Heathkit shop board, you have exposed voltages 
on the top of the chassis.

I personally prefer the Heathkitshop board, but it was designed for the AC4.  
It is your call, but if you do use the board on an AC3, please make some type 
of cover, or make other accommodations for safety.  Death is permanent.

73,
Ron WD8SBB

--- On Sat, 3/10/12, K3VX  wrote:

From: K3VX 
Subject: [Drakelist] AC3 vs AC4
To: drakelist@zerobeat.net
Date: Saturday, March 10, 2012, 10:40 AM

I have an AC-4 but the documentation that came with  the T4-X is for the AC3.

All the electrolytic caps have to be replaced as well as some other parts. 

Differences between the models?? Also sources for the caps?

Thanks for any help you can give.

Larry K3VX, VP2MVX, 8P9VX



-Inline Attachment Follows-

___
Drakelist mailing list
Drakelist@zerobeat.net
http://mailman.zerobeat.net/mailman/listinfo/drakelist
___
Drakelist mailing list
Drakelist@zerobeat.net
http://mailman.zerobeat.net/mailman/listinfo/drakelist

Re: [Drakelist] AC3 vs AC4

[kc9cdt]

Larry,
I would use the Heathkit Shop replacement board...works great...easy to 
do.

I have done 3 of them.
73,
Lee



-Original Message-
From: K3VX 
To: drakelist 
Sent: Sat, Mar 10, 2012 10:46 am
Subject: [Drakelist] AC3 vs AC4


I have an AC-4 but the documentation that came with  the T4-X is for 
the AC3.


All the electrolytic caps have to be replaced as well as some other 
parts.


Differences between the models?? Also sources for the caps?

Thanks for any help you can give.

Larry K3VX, VP2MVX, 8P9VX


___
Drakelist mailing list
Drakelist@zerobeat.net
http://mailman.zerobeat.net/mailman/listinfo/drakelist


___
Drakelist mailing list
Drakelist@zerobeat.net
http://mailman.zerobeat.net/mailman/listinfo/drakelist

Re: [Drakelist] AC3 vs AC4

[Mark Pilant]

Hi Larry.

As Garey said you can to an original style rebuild using the Hayseed
Hamfest parts.  Here is a page I put together showing my AC-4 rebuild:

http://www.n1vqw.net/ac4rebuild/

As for the AC-4 documentation, it is available in a number of places
on the web.  Usually as part of the TR-4 (and probably other T-4..
rigs.)

73

- Mark  N1VQW

___
Drakelist mailing list
Drakelist@zerobeat.net
http://mailman.zerobeat.net/mailman/listinfo/drakelist

Re: [Drakelist] AC3 vs AC4

[Garey Barrell]

Larry -

Simplest is the AC-4R from www.heathkitshop.com which replaces all active components.  If you want 
to keep it 'original', new 'Twist-lok' style caps are available from www.hayseedhamfest.com.



73, Garey - K4OAH
Glen Allen, VA

Drake 2-B, 2-C/2-NT, 4-A, 4-B, C-Line
and TR-4/C Service Supplement CDs



K3VX wrote:

I have an AC-4 but the documentation that came with  the T4-X is for the AC3.

All the electrolytic caps have to be replaced as well as some other parts.

Differences between the models?? Also sources for the caps?

Thanks for any help you can give.

Larry K3VX, VP2MVX, 8P9VX



___
Drakelist mailing list
Drakelist@zerobeat.net
http://mailman.zerobeat.net/mailman/listinfo/drakelist

[Drakelist] AC3 vs AC4

[K3VX]

I have an AC-4 but the documentation that came with  the T4-X is for the AC3.All the electrolytic caps have to be replaced as well as some other parts. Differences between the models?? Also sources for the caps?Thanks for any help you can give.Larry K3VX, VP2MVX, 8P9VX

___
Drakelist mailing list
Drakelist@zerobeat.net
http://mailman.zerobeat.net/mailman/listinfo/drakelist

Re: [drakelist] AC3 VS AC4

[ARDUJENSKI]

Gary
I am so glad I asked the question and especially appreciative that you took  
the time to clarify the issue. I am sure there are many folks thinking the 
same  thing right now. I visited your website and was not aware of the CDs you 
make  available. WOW this was like an inside the park home run!
 
Thank you
 
Alan KB7MBI
Woodinville, WA
===
 
 
In a message dated 12/13/2007 11:46:14 A.M. Pacific Standard Time,  
[EMAIL PROTECTED] writes:


Garey Barrell <[EMAIL PROTECTED]> made an utterance to the  drakelist  gang
--
Alan  -

The AC-3, (with the exception of a very few early units,) is  
functionally identical with the AC-4.

The fault that makes an AC-3  "cook a set of finals" is exactly the same 
fault that can cause an AC-4 to  do the same!  This "fault" is a failure 
of the bias portion of the  power supply, which is identical in both 
supplies.  The bias supply  is by far the most "critical" part of the 
AC-3/4.  It is used to keep  the T/R relay in the standby condition, and 
limits the idle current drawn  by the final tubes in transmit, among 
other things.

The failure  mode is this.  One or both of the filter capacitors in 
the bias  supply of the AC-3/4 dries out.  The "early warning", if you're  
lucky, is erratic VOX operation, the VOX taking longer to drop out than  
it should, or increasing idle current in the final.  If you're NOT  
lucky, like most of us, one of the filter caps will short, killing the  
bias supply completely.  Even if the transmitter is in standby, while  
you have gone to the kitchen for a snack, or to a hamfest, when the bias  
supply fails the T-R relay will close, putting the transmitter in  
transmit.  Since there is no bias, the final tubes will draw as much  
current as they can until either one of the final tubes melts, shorting  
the HV supply, and hopefully blowing the power supply fuse, (assuming  
you or a previous owner hasn't replaced it with a piece of #000 copper  
wire,) or burning up the transmitter, power supply and/or  house!   
Alarmist?  Yeah.  You wanna take the  chance?  Didn't think so...

At the very least, with a "new" or  unknown, or even a supply you've had 
"for years", replace the filter caps  on the bias supply NOW if they 
haven't already been replaced within the  last 10 years.  Better yet, 
upgrade your AC-3/4 with the AC-4R kit  from Mike at The Heathkit Shop, 
and forget about it for another 30 years  or so.  Also, check that the 
fuse is either 5 or 6A Slo-Blo.   Early supplies are marked 5A, but 
tended to blow from the turn-on surge  and so was increased to 6A.

Finally, (at last,) the answer to your  question  Yes, the supplies 
are fully interchangeable across the  4 Line.  The AC-3 doesn't have the 
VOX connector to key a linear  amplifier, since the AC-3 was for the TR-3 
and very few people wanted to  put a linear behind a transmitter that put 
out 200 W.  The little RCA  jack pigtail coming out of the back of the PS 
connector was originally  wired for the speaker with the TR-3 or TR-4.  
If you need an external  VOX jack, the easiest way is to add another RCA 
pigtail in the Cinch  connector.

73, Garey - K4OAH
Glen Allen, VA

Drake 2-B, 4-B  & C-Line Service Supplement  CDs




[EMAIL PROTECTED] wrote:
>  [EMAIL PROTECTED] made an utterance to the drakelist gang
>  --
>  I was trying to find out if the AC3 power supply  can be used with the  
T-4 
> series transmitters or whether the AC4 is necessary.   Searching the Drake 
> archives I stumbled across one of the few  postings  addressing the subject:
>  LIST  
>  POSTING-
>
>> Does anyone know if  there is a differnce between the Drake  AC-4 and 
>> AC-3 power supplies  electrical wise in the  connector? I have both and 
>> the AC-4 works fine  but the AC-3  seemed to cause various problems 
including 
>> cooking a set of   finals in a T4XB. Seems like it causes the T4XB and 
T4XC 
>> to go  into  transmit part of the time.  
>>  
>  
--
>  -
> I  was hoping to get a clarification  from this list.
>
> Thank you
>
> Alan   KB7MBI  
>
>
>

--
Submissions:   [EMAIL PROTECTED]
Unsubscribe: [EMAIL PROTECTED] - unsubscribe drakelist in  body
Hopelessly Lost:[EMAIL PROTECTED] - help in body of  message
Zerobeat Web Page:  www.zerobeat.net - sponsored by  www.tlchost.net
--





**See AOL's top rated recipes 
(http://food.aol.com/top-rated-recipes?NCID=aoltop000304)

Re: [drakelist] AC3 VS AC4

[n0tu/Steve]

"n0tu/Steve" <[EMAIL PROTECTED]> made an utterance to the drakelist gang
--
Thanks Garey!  Sounds like that bias supply is the Achilles heel of
the Drake PSs!

2007/12/13 Peter Bent <[EMAIL PROTECTED]>:
>
> "Peter Bent" <[EMAIL PROTECTED]> made an utterance to the drakelist gang
> --
> Thanks Mike,
> Good warning... I had no idea.. I'm going to order the kit.
>
>
> -Original Message-
> From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
> Behalf Of Garey Barrell
> Sent: Thursday, December 13, 2007 2:46 PM
> To: [EMAIL PROTECTED]
> Subject: Re: [drakelist] AC3 VS AC4
>
>
> Garey Barrell <[EMAIL PROTECTED]> made an utterance to the drakelist gang
> --
> Alan -
>
> The AC-3, (with the exception of a very few early units,) is
> functionally identical with the AC-4.
>
> The fault that makes an AC-3 "cook a set of finals" is exactly the same
> fault that can cause an AC-4 to do the same!  This "fault" is a failure
> of the bias portion of the power supply, which is identical in both
> supplies.  The bias supply is by far the most "critical" part of the
> AC-3/4.  It is used to keep the T/R relay in the standby condition, and
> limits the idle current drawn by the final tubes in transmit, among
> other things.
>
> The failure mode is this.  One or both of the filter capacitors in
> the bias supply of the AC-3/4 dries out.  The "early warning", if you're
> lucky, is erratic VOX operation, the VOX taking longer to drop out than
> it should, or increasing idle current in the final.  If you're NOT
> lucky, like most of us, one of the filter caps will short, killing the
> bias supply completely.  Even if the transmitter is in standby, while
> you have gone to the kitchen for a snack, or to a hamfest, when the bias
> supply fails the T-R relay will close, putting the transmitter in
> transmit.  Since there is no bias, the final tubes will draw as much
> current as they can until either one of the final tubes melts, shorting
> the HV supply, and hopefully blowing the power supply fuse, (assuming
> you or a previous owner hasn't replaced it with a piece of #000 copper
> wire,) or burning up the transmitter, power supply and/or house!
> Alarmist?  Yeah.  You wanna take the chance?  Didn't think so...
>
> At the very least, with a "new" or unknown, or even a supply you've had
> "for years", replace the filter caps on the bias supply NOW if they
> haven't already been replaced within the last 10 years.  Better yet,
> upgrade your AC-3/4 with the AC-4R kit from Mike at The Heathkit Shop,
> and forget about it for another 30 years or so.  Also, check that the
> fuse is either 5 or 6A Slo-Blo.  Early supplies are marked 5A, but
> tended to blow from the turn-on surge and so was increased to 6A.
>
> Finally, (at last,) the answer to your question  Yes, the supplies
> are fully interchangeable across the 4 Line.  The AC-3 doesn't have the
> VOX connector to key a linear amplifier, since the AC-3 was for the TR-3
> and very few people wanted to put a linear behind a transmitter that put
> out 200 W.  The little RCA jack pigtail coming out of the back of the PS
> connector was originally wired for the speaker with the TR-3 or TR-4.
> If you need an external VOX jack, the easiest way is to add another RCA
> pigtail in the Cinch connector.
>
> 73, Garey - K4OAH
> Glen Allen, VA
>
> Drake 2-B, 4-B & C-Line Service Supplement CDs
> 
>
>
>
> [EMAIL PROTECTED] wrote:
> > [EMAIL PROTECTED] made an utterance to the drakelist gang
> > --
> > I was trying to find out if the AC3 power supply  can be used with the T-4
>
> > series transmitters or whether the AC4 is necessary.  Searching the Drake
> > archives I stumbled across one of the few postings  addressing the
> subject:
> > LIST
> > POSTING-
> >
> >> Does anyone know if  there is a differnce between the Drake AC-4 and
> >> AC-3 power supplies  electrical wise in the connector? I have both and
> >> the AC-4 works fine  but the AC-3 seemed to cause various problems
> including
> >> cooking a set of  finals in a T4XB. Seems like it causes the T4XB and
> T4XC
> >> to go into  transmit part of the time.
> >>
> >
> 

RE: [drakelist] AC3 VS AC4

[Peter Bent]

"Peter Bent" <[EMAIL PROTECTED]> made an utterance to the drakelist gang
--
Thanks Mike,
Good warning... I had no idea.. I'm going to order the kit.

-Original Message-
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Garey Barrell
Sent: Thursday, December 13, 2007 2:46 PM
To: [EMAIL PROTECTED]
Subject: Re: [drakelist] AC3 VS AC4


Garey Barrell <[EMAIL PROTECTED]> made an utterance to the drakelist gang
--
Alan -

The AC-3, (with the exception of a very few early units,) is 
functionally identical with the AC-4.

The fault that makes an AC-3 "cook a set of finals" is exactly the same 
fault that can cause an AC-4 to do the same!  This "fault" is a failure 
of the bias portion of the power supply, which is identical in both 
supplies.  The bias supply is by far the most "critical" part of the 
AC-3/4.  It is used to keep the T/R relay in the standby condition, and 
limits the idle current drawn by the final tubes in transmit, among 
other things.

The failure mode is this.  One or both of the filter capacitors in 
the bias supply of the AC-3/4 dries out.  The "early warning", if you're 
lucky, is erratic VOX operation, the VOX taking longer to drop out than 
it should, or increasing idle current in the final.  If you're NOT 
lucky, like most of us, one of the filter caps will short, killing the 
bias supply completely.  Even if the transmitter is in standby, while 
you have gone to the kitchen for a snack, or to a hamfest, when the bias 
supply fails the T-R relay will close, putting the transmitter in 
transmit.  Since there is no bias, the final tubes will draw as much 
current as they can until either one of the final tubes melts, shorting 
the HV supply, and hopefully blowing the power supply fuse, (assuming 
you or a previous owner hasn't replaced it with a piece of #000 copper 
wire,) or burning up the transmitter, power supply and/or house!   
Alarmist?  Yeah.  You wanna take the chance?  Didn't think so...

At the very least, with a "new" or unknown, or even a supply you've had 
"for years", replace the filter caps on the bias supply NOW if they 
haven't already been replaced within the last 10 years.  Better yet, 
upgrade your AC-3/4 with the AC-4R kit from Mike at The Heathkit Shop, 
and forget about it for another 30 years or so.  Also, check that the 
fuse is either 5 or 6A Slo-Blo.  Early supplies are marked 5A, but 
tended to blow from the turn-on surge and so was increased to 6A.

Finally, (at last,) the answer to your question  Yes, the supplies 
are fully interchangeable across the 4 Line.  The AC-3 doesn't have the 
VOX connector to key a linear amplifier, since the AC-3 was for the TR-3 
and very few people wanted to put a linear behind a transmitter that put 
out 200 W.  The little RCA jack pigtail coming out of the back of the PS 
connector was originally wired for the speaker with the TR-3 or TR-4.  
If you need an external VOX jack, the easiest way is to add another RCA 
pigtail in the Cinch connector.

73, Garey - K4OAH
Glen Allen, VA

Drake 2-B, 4-B & C-Line Service Supplement CDs




[EMAIL PROTECTED] wrote:
> [EMAIL PROTECTED] made an utterance to the drakelist gang
> --
> I was trying to find out if the AC3 power supply  can be used with the T-4

> series transmitters or whether the AC4 is necessary.  Searching the Drake 
> archives I stumbled across one of the few postings  addressing the
subject:
> LIST  
> POSTING-
>   
>> Does anyone know if  there is a differnce between the Drake AC-4 and 
>> AC-3 power supplies  electrical wise in the connector? I have both and 
>> the AC-4 works fine  but the AC-3 seemed to cause various problems
including 
>> cooking a set of  finals in a T4XB. Seems like it causes the T4XB and
T4XC 
>> to go into  transmit part of the time.  
>> 
>

--
> -
> I  was hoping to get a clarification from this list.
>
> Thank you
>
> Alan  KB7MBI  
>
>
>   

--
Submissions:[EMAIL PROTECTED]
Unsubscribe:[EMAIL PROTECTED] - unsubscribe drakelist in body
Hopelessly Lost:[EMAIL PROTECTED] - help in body of message
Zerobeat Web Page:  www.zerobeat.net - sponsored by www.tlchost.net
--



--
Submiss

Re: [drakelist] AC3 VS AC4

[Boyd Van Horn]

Garey, Have you had any experience with attaching an old Heathkit Warrior 
Linear to a Drake TR4-C? Sincerely, Boyd W0BUW

Garey Barrell <[EMAIL PROTECTED]> wrote:  
Garey Barrell made an utterance to the drakelist gang
--
Alan -

The AC-3, (with the exception of a very few early units,) is 
functionally identical with the AC-4.

The fault that makes an AC-3 "cook a set of finals" is exactly the same 
fault that can cause an AC-4 to do the same! This "fault" is a failure 
of the bias portion of the power supply, which is identical in both 
supplies. The bias supply is by far the most "critical" part of the 
AC-3/4. It is used to keep the T/R relay in the standby condition, and 
limits the idle current drawn by the final tubes in transmit, among 
other things.

The failure mode is this. One or both of the filter capacitors in 
the bias supply of the AC-3/4 dries out. The "early warning", if you're 
lucky, is erratic VOX operation, the VOX taking longer to drop out than 
it should, or increasing idle current in the final. If you're NOT 
lucky, like most of us, one of the filter caps will short, killing the 
bias supply completely. Even if the transmitter is in standby, while 
you have gone to the kitchen for a snack, or to a hamfest, when the bias 
supply fails the T-R relay will close, putting the transmitter in 
transmit. Since there is no bias, the final tubes will draw as much 
current as they can until either one of the final tubes melts, shorting 
the HV supply, and hopefully blowing the power supply fuse, (assuming 
you or a previous owner hasn't replaced it with a piece of #000 copper 
wire,) or burning up the transmitter, power supply and/or house! 
Alarmist? Yeah. You wanna take the chance? Didn't think so...

At the very least, with a "new" or unknown, or even a supply you've had 
"for years", replace the filter caps on the bias supply NOW if they 
haven't already been replaced within the last 10 years. Better yet, 
upgrade your AC-3/4 with the AC-4R kit from Mike at The Heathkit Shop, 
and forget about it for another 30 years or so. Also, check that the 
fuse is either 5 or 6A Slo-Blo. Early supplies are marked 5A, but 
tended to blow from the turn-on surge and so was increased to 6A.

Finally, (at last,) the answer to your question Yes, the supplies 
are fully interchangeable across the 4 Line. The AC-3 doesn't have the 
VOX connector to key a linear amplifier, since the AC-3 was for the TR-3 
and very few people wanted to put a linear behind a transmitter that put 
out 200 W. The little RCA jack pigtail coming out of the back of the PS 
connector was originally wired for the speaker with the TR-3 or TR-4. 
If you need an external VOX jack, the easiest way is to add another RCA 
pigtail in the Cinch connector.

73, Garey - K4OAH
Glen Allen, VA

Drake 2-B, 4-B & C-Line Service Supplement CDs




[EMAIL PROTECTED] wrote:
> [EMAIL PROTECTED] made an utterance to the drakelist gang
> --
> I was trying to find out if the AC3 power supply can be used with the T-4 
> series transmitters or whether the AC4 is necessary. Searching the Drake 
> archives I stumbled across one of the few postings addressing the subject:
> LIST 
> POSTING-
> 
>> Does anyone know if there is a differnce between the Drake AC-4 and 
>> AC-3 power supplies electrical wise in the connector? I have both and 
>> the AC-4 works fine but the AC-3 seemed to cause various problems including 
>> cooking a set of finals in a T4XB. Seems like it causes the T4XB and T4XC 
>> to go into transmit part of the time. 
>> 
> --
> -
> I was hoping to get a clarification from this list.
>
> Thank you
>
> Alan KB7MBI 
>
>
> 

--
Submissions: [EMAIL PROTECTED]
Unsubscribe: [EMAIL PROTECTED] - unsubscribe drakelist in body
Hopelessly Lost: [EMAIL PROTECTED] - help in body of message
Zerobeat Web Page: www.zerobeat.net - sponsored by www.tlchost.net
--

Re: [drakelist] AC3 VS AC4

[Garey Barrell]

Garey Barrell <[EMAIL PROTECTED]> made an utterance to the drakelist gang
--
Alan -

The AC-3, (with the exception of a very few early units,) is 
functionally identical with the AC-4.


The fault that makes an AC-3 "cook a set of finals" is exactly the same 
fault that can cause an AC-4 to do the same!  This "fault" is a failure 
of the bias portion of the power supply, which is identical in both 
supplies.  The bias supply is by far the most "critical" part of the 
AC-3/4.  It is used to keep the T/R relay in the standby condition, and 
limits the idle current drawn by the final tubes in transmit, among 
other things.


The failure mode is this.  One or both of the filter capacitors in 
the bias supply of the AC-3/4 dries out.  The "early warning", if you're 
lucky, is erratic VOX operation, the VOX taking longer to drop out than 
it should, or increasing idle current in the final.  If you're NOT 
lucky, like most of us, one of the filter caps will short, killing the 
bias supply completely.  Even if the transmitter is in standby, while 
you have gone to the kitchen for a snack, or to a hamfest, when the bias 
supply fails the T-R relay will close, putting the transmitter in 
transmit.  Since there is no bias, the final tubes will draw as much 
current as they can until either one of the final tubes melts, shorting 
the HV supply, and hopefully blowing the power supply fuse, (assuming 
you or a previous owner hasn't replaced it with a piece of #000 copper 
wire,) or burning up the transmitter, power supply and/or house!   
Alarmist?  Yeah.  You wanna take the chance?  Didn't think so...


At the very least, with a "new" or unknown, or even a supply you've had 
"for years", replace the filter caps on the bias supply NOW if they 
haven't already been replaced within the last 10 years.  Better yet, 
upgrade your AC-3/4 with the AC-4R kit from Mike at The Heathkit Shop, 
and forget about it for another 30 years or so.  Also, check that the 
fuse is either 5 or 6A Slo-Blo.  Early supplies are marked 5A, but 
tended to blow from the turn-on surge and so was increased to 6A.


Finally, (at last,) the answer to your question  Yes, the supplies 
are fully interchangeable across the 4 Line.  The AC-3 doesn't have the 
VOX connector to key a linear amplifier, since the AC-3 was for the TR-3 
and very few people wanted to put a linear behind a transmitter that put 
out 200 W.  The little RCA jack pigtail coming out of the back of the PS 
connector was originally wired for the speaker with the TR-3 or TR-4.  
If you need an external VOX jack, the easiest way is to add another RCA 
pigtail in the Cinch connector.


73, Garey - K4OAH
Glen Allen, VA

Drake 2-B, 4-B & C-Line Service Supplement CDs




[EMAIL PROTECTED] wrote:

[EMAIL PROTECTED] made an utterance to the drakelist gang
--
I was trying to find out if the AC3 power supply  can be used with the T-4 
series transmitters or whether the AC4 is necessary.  Searching the Drake 
archives I stumbled across one of the few postings  addressing the subject:
LIST  
POSTING-
  
Does anyone know if  there is a differnce between the Drake AC-4 and 
AC-3 power supplies  electrical wise in the connector? I have both and 
the AC-4 works fine  but the AC-3 seemed to cause various problems including 
cooking a set of  finals in a T4XB. Seems like it causes the T4XB and T4XC 
to go into  transmit part of the time.  


--
-
I  was hoping to get a clarification from this list.

Thank you

Alan  KB7MBI  



  


--
Submissions:[EMAIL PROTECTED]
Unsubscribe:[EMAIL PROTECTED] - unsubscribe drakelist in body
Hopelessly Lost:[EMAIL PROTECTED] - help in body of message
Zerobeat Web Page:  www.zerobeat.net - sponsored by www.tlchost.net
--

Re: [drakelist] AC3 VS AC4

[n0tu/Steve]

"n0tu/Steve" <[EMAIL PROTECTED]> made an utterance to the drakelist gang
--
I could be wrong Alan but so long as you adjust the bias correctly
with the AC3 it should work w/T4, T4XB, and C series? If I'm wrong
then I'm in trouble cause I occasionally use a AC3 to run my T4XC??
Steve/n0tu

2007/12/13  <[EMAIL PROTECTED]>:
>
> [EMAIL PROTECTED] made an utterance to the drakelist gang
> --
> I was trying to find out if the AC3 power supply  can be used with the T-4
> series transmitters or whether the AC4 is necessary.  Searching the Drake
> archives I stumbled across one of the few postings  addressing the subject:
> LIST
> POSTING-
> >Does anyone know if  there is a differnce between the Drake AC-4 and
> >AC-3 power supplies  electrical wise in the connector? I have both and
> >the AC-4 works fine  but the AC-3 seemed to cause various problems including
> >cooking a set of  finals in a T4XB. Seems like it causes the T4XB and T4XC
> >to go into  transmit part of the time.
> --
> -
> I  was hoping to get a clarification from this list.
>
> Thank you
>
> Alan  KB7MBI
>
>
>
>
> **See AOL's top rated recipes
> (http://food.aol.com/top-rated-recipes?NCID=aoltop000304)
>
> --
> Submissions:[EMAIL PROTECTED]
> Unsubscribe:[EMAIL PROTECTED] - unsubscribe drakelist in body
> Hopelessly Lost:[EMAIL PROTECTED] - help in body of message
> Zerobeat Web Page:  www.zerobeat.net - sponsored by www.tlchost.net
> --
>

--
Submissions:[EMAIL PROTECTED]
Unsubscribe:[EMAIL PROTECTED] - unsubscribe drakelist in body
Hopelessly Lost:[EMAIL PROTECTED] - help in body of message
Zerobeat Web Page:  www.zerobeat.net - sponsored by www.tlchost.net
--

[drakelist] AC3 VS AC4

[ARDUJENSKI]

[EMAIL PROTECTED] made an utterance to the drakelist gang
--
I was trying to find out if the AC3 power supply  can be used with the T-4 
series transmitters or whether the AC4 is necessary.  Searching the Drake 
archives I stumbled across one of the few postings  addressing the subject:
LIST  
POSTING-
>Does anyone know if  there is a differnce between the Drake AC-4 and 
>AC-3 power supplies  electrical wise in the connector? I have both and 
>the AC-4 works fine  but the AC-3 seemed to cause various problems including 
>cooking a set of  finals in a T4XB. Seems like it causes the T4XB and T4XC 
>to go into  transmit part of the time.  
--
-
I  was hoping to get a clarification from this list.

Thank you

Alan  KB7MBI  




**See AOL's top rated recipes 
(http://food.aol.com/top-rated-recipes?NCID=aoltop000304)

--
Submissions:[EMAIL PROTECTED]
Unsubscribe:[EMAIL PROTECTED] - unsubscribe drakelist in body
Hopelessly Lost:[EMAIL PROTECTED] - help in body of message
Zerobeat Web Page:  www.zerobeat.net - sponsored by www.tlchost.net
--

RE: [drakelist] AC3 vs AC4 ?

[Ron Wagner]

Ron Wagner <[EMAIL PROTECTED]> made an utterance to the drakelist gang
--
I errored, TP1 is in the plate supply line as Gary states.

It will measure plate current indirectly via way of voltage drop across a 
known resistance.  The TR3 manual, which includes the AC3 in it, will 
tell you exactly how to use it.  I think BAMA has the TR3 manual.


73,
Ron

On Wed, 4 Jan 2006, W7RY wrote:



"W7RY" <[EMAIL PROTECTED]> made an utterance to the drakelist gang
--
The measuring point is not in the bias line.

It is actually in the plate supply line. You cannot measure plate
current, (idling current is adjusted by the bias level. Not measured
there) while in series with the bias line.

73
Jim W7RY




--
Submissions:drakelist@www.zerobeat.net
Unsubscribe:[EMAIL PROTECTED] - unsubscribe drakelist in body
Hopelessly Lost:[EMAIL PROTECTED] - help in body of message
Zerobeat Web Page:  www.zerobeat.net - sponsored by www.tlchost.net
--

RE: [drakelist] AC3 vs AC4 ?

[W7RY]

"W7RY" <[EMAIL PROTECTED]> made an utterance to the drakelist gang
--
The measuring point is not in the bias line.

It is actually in the plate supply line. You cannot measure plate
current, (idling current is adjusted by the bias level. Not measured
there) while in series with the bias line.

73
Jim W7RY



-Original Message-
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] On Behalf Of Garey Barrell
Sent: Wednesday, January 04, 2006 8:54 AM
To: drakelist
Subject: Re: [drakelist] AC3 vs AC4 ?


Garey Barrell <[EMAIL PROTECTED]> made an utterance to the drakelist
gang
--
Ron -

Absolutely.   I don't think I ever used the jumper method once the power
supply was installed in the speaker cabinet though...  :-)

Yeah, I think we've "slightly" exceeded the original 25 word
limit

73, Garey - K4OAH
Atlanta

Drake C-Line Service Manual
<http://www.k4oah.com>



Ron Wagner wrote:

> One big difference is that the AC3 has a set of resistors in the bias 
> line.  Those resistors are jumper shorted out normally with a small 
> screw. Lifting the jumper short allows you to easily measure the idle 
> current (actually voltage across known resistance).  Much easier then 
> trying to look at the fat needle against fat marking.
>
> You can measure the current on the resistor under the chassis too, and

> should to make sure the finals are balanced.  But to set the current 
> easily the AC3 was a gem.  IMHO.
>
> Okay, something of a thesis.  :-)
>
> 73,
> Ron
>
> 
> Visit my astronomy home page.   http://www.dma.org/~wagner
> Amateur Radio Station: WD8SBB - Ron  and  KB8NRP - Joann
> 
>
> On Tue, 3 Jan 2006, Garey Barrell wrote:
>
>>
>> Garey Barrell <[EMAIL PROTECTED]> made an utterance to the 
>> drakelist gang
>>
--
>> Functionally identical.  Electrically "almost" identical.  Only real 
>> difference is the age of the components.
>>
>> 14 words, not counting the sig!
>>
>> 73, Garey - K4OAH
>> Atlanta
>>
>> Drake C-Line Service Manual
>> <http://www.k4oah.com>
>>
>>
>>
>> chuck grandgent wrote:
>>
>>> chuck grandgent <[EMAIL PROTECTED]> made an utterance to the 
>>> drakelist gang
>>>
--
>>> OK, simple question.
>>> In 25 words or less, what's the diff between AC3 and AC4 ?
>>> I've seen schematics, is the AC4 just a slightly more progressive 
>>> design ?
>>>
>>> Thanx,
>>>   Chuck, K1OM
>>>
>>>
>>
--
>> Submissions:drakelist@www.zerobeat.net
>> Unsubscribe:[EMAIL PROTECTED] - unsubscribe 
>> drakelist in body
>> Hopelessly Lost:[EMAIL PROTECTED] - help in body of
message
>> Zerobeat Web Page:  www.zerobeat.net - sponsored by www.tlchost.net
>>
--
>>
>

--
Submissions:drakelist@www.zerobeat.net
Unsubscribe:[EMAIL PROTECTED] - unsubscribe drakelist
in body
Hopelessly Lost:[EMAIL PROTECTED] - help in body of message
Zerobeat Web Page:  www.zerobeat.net - sponsored by www.tlchost.net
--

--
Submissions:drakelist@www.zerobeat.net
Unsubscribe:[EMAIL PROTECTED] - unsubscribe drakelist in body
Hopelessly Lost:[EMAIL PROTECTED] - help in body of message
Zerobeat Web Page:  www.zerobeat.net - sponsored by www.tlchost.net
--

Re: [drakelist] AC3 vs AC4 ?

[Garey Barrell]

Garey Barrell <[EMAIL PROTECTED]> made an utterance to the drakelist gang
--
Ron / Jason -

The resistor is 5 ohms @ 2W, so should read 0.5 VDC for the recommended 
0.1A idle current.  The plate meter "should" also read 0.1A.


Actually, I'm not really sure why they bothered to short out the 
resistor.  It's actually in the negative lead of the HV supply, and even 
at full plate current there is less than 2 V drop across the resistor.   
Not that big a difference in the 650 VDC supply voltage, considering the 
supply drops about 50 V from no load to full load.


73, Garey - K4OAH
Atlanta

Drake C-Line Service Manual




Ron Wagner wrote:



Ron Wagner <[EMAIL PROTECTED]> made an utterance to the drakelist gang
--
Jason,
I am not sure what you mean about measuring below the chassis.

- I couldn't make heads or tails of the TP-1 reading with the jumper 
screw

removed.



You need to measure the *voltage* from TP1 to ground (TP1 ungrounded 
of course).  There is actually a voltage drop over a resistor below 
the chassis.  That voltage is directly related to the current flowing 
through the resistor.   I don't have the TR3 manual handy, so I can 
not tell you exactly what voltage ratio would be.  But the voltage has 
a direct relation to the plate meter reading.


Ohms law says current is equal to voltage divided by resistance.  And 
what ever the values give, that is the current.  Idle is all that 
should be measured this way as leaving it ungrounded will create 
distortion as the bias voltage will change as the voice peaks draw 
more/less current.


As for being inside the MS4, well I had to remove the AC3 to change 
bias any way. And you did this how often?  :-)  How lazy are we?  :-)


See the two pictures at this link:  http://www.dma.org/~wagner/ac3.htm

The TP1 is to the right and a bit up from the bias pot, between filter 
caps.  It used a screw from the filter cap to ground the TP.  Second 
pic is side view.


Hope this makes everything "as clear as mud"  :-)

73,
Ron


--
Submissions:drakelist@www.zerobeat.net
Unsubscribe:[EMAIL PROTECTED] - unsubscribe drakelist in body
Hopelessly Lost:[EMAIL PROTECTED] - help in body of message
Zerobeat Web Page:  www.zerobeat.net - sponsored by www.tlchost.net
--

Re: [drakelist] AC3 vs AC4 ?

[Ron Wagner]

Ron Wagner <[EMAIL PROTECTED]> made an utterance to the drakelist gang
--
Jason,
I am not sure what you mean about measuring below the chassis.


- I couldn't make heads or tails of the TP-1 reading with the jumper screw
removed.



You need to measure the *voltage* from TP1 to ground (TP1 ungrounded of 
course).  There is actually a voltage drop over a resistor below the 
chassis.  That voltage is directly related to the current flowing through 
the resistor.   I don't have the TR3 manual handy, so I can not tell you 
exactly what voltage ratio would be.  But the voltage has a direct 
relation to the plate meter reading.


Ohms law says current is equal to voltage divided by resistance.  And what 
ever the values give, that is the current.  Idle is all that should be 
measured this way as leaving it ungrounded will create distortion as the 
bias voltage will change as the voice peaks draw more/less current.


As for being inside the MS4, well I had to remove the AC3 to change bias 
any way. And you did this how often?  :-)  How lazy are we?  :-)


See the two pictures at this link:  http://www.dma.org/~wagner/ac3.htm

The TP1 is to the right and a bit up from the bias pot, between filter 
caps.  It used a screw from the filter cap to ground the TP.  Second pic 
is side view.


Hope this makes everything "as clear as mud"  :-)

73,
Ron


Visit my astronomy home page.   http://www.dma.org/~wagner
Amateur Radio Station: WD8SBB - Ron  and  KB8NRP - Joann



--
Submissions:drakelist@www.zerobeat.net
Unsubscribe:[EMAIL PROTECTED] - unsubscribe drakelist in body
Hopelessly Lost:[EMAIL PROTECTED] - help in body of message
Zerobeat Web Page:  www.zerobeat.net - sponsored by www.tlchost.net
--

Re: [drakelist] AC3 vs AC4 ?

[Don and Diana Cunningham]

"Don and Diana Cunningham" <[EMAIL PROTECTED]> made an utterance to the 
drakelist gang
--
Who set the 25 word limit, Garey??  Hi Hi.  I, for one, enjoy reading what 
you and others have to share with us on many topics and learn from each one. 
I hadn't noticed the "jumper method" of checking bias in the AC3, so that's 
nice to know too.  Would be difficult in the speaker cabinet though, for 
sure, hi.

73 and Happy New Year!
Don, WB5HAK 


--
Submissions:drakelist@www.zerobeat.net
Unsubscribe:[EMAIL PROTECTED] - unsubscribe drakelist in body
Hopelessly Lost:[EMAIL PROTECTED] - help in body of message
Zerobeat Web Page:  www.zerobeat.net - sponsored by www.tlchost.net
--

Re: [drakelist] AC3 vs AC4 ?

[jsb]

[EMAIL PROTECTED] made an utterance to the drakelist gang
--
On Wed, 4 Jan 2006, Ron Wagner wrote:

> One big difference is that the AC3 has a set of resistors in the bias
> line.  Those resistors are jumper shorted out normally with a small
> screw.  Lifting the jumper short allows you to easily measure the idle
> current (actually voltage across known resistance).  Much easier then
> trying to look at the fat needle against fat marking.
>
> You can measure the current on the resistor under the chassis too, and
> should to make sure the finals are balanced.  But to set the current
> easily the AC3 was a gem.  IMHO.

You touched on something that I noticed when I was trying to align the
bias current on my AC-3 (and haven't tried yet with AC-4)...  I wound up
leaving the screw connected and measuring the voltage off of the
connection to the filter C (will have to review the schematic to tell you
which one).  Can this same trick be used on the AC-4 or is this an AC-3
only operation?  I had to pull the bottom cover off of the AC-3 to do this
- I couldn't make heads or tails of the TP-1 reading with the jumper screw
removed.

Thanks!

--
73 Jason N1SU
http://n1su.com/
--
Submissions:drakelist@www.zerobeat.net
Unsubscribe:[EMAIL PROTECTED] - unsubscribe drakelist in body
Hopelessly Lost:[EMAIL PROTECTED] - help in body of message
Zerobeat Web Page:  www.zerobeat.net - sponsored by www.tlchost.net
--

Re: [drakelist] AC3 vs AC4 ?

[Garey Barrell]

Garey Barrell <[EMAIL PROTECTED]> made an utterance to the drakelist gang
--
Ron -

Absolutely.   I don't think I ever used the jumper method once the power
supply was installed in the speaker cabinet though...  :-)

Yeah, I think we've "slightly" exceeded the original 25 word limit

73, Garey - K4OAH
Atlanta

Drake C-Line Service Manual




Ron Wagner wrote:

One big difference is that the AC3 has a set of resistors in the bias 
line.  Those resistors are jumper shorted out normally with a small 
screw. Lifting the jumper short allows you to easily measure the idle 
current (actually voltage across known resistance).  Much easier then 
trying to look at the fat needle against fat marking.


You can measure the current on the resistor under the chassis too, and 
should to make sure the finals are balanced.  But to set the current 
easily the AC3 was a gem.  IMHO.


Okay, something of a thesis.  :-)

73,
Ron


Visit my astronomy home page.   http://www.dma.org/~wagner
Amateur Radio Station: WD8SBB - Ron  and  KB8NRP - Joann


On Tue, 3 Jan 2006, Garey Barrell wrote:



Garey Barrell <[EMAIL PROTECTED]> made an utterance to the 
drakelist gang

--
Functionally identical.  Electrically "almost" identical.  Only real 
difference is the age of the components.


14 words, not counting the sig!

73, Garey - K4OAH
Atlanta

Drake C-Line Service Manual




chuck grandgent wrote:

chuck grandgent <[EMAIL PROTECTED]> made an utterance to the 
drakelist gang

--
OK, simple question.
In 25 words or less, what's the diff between AC3 and AC4 ?
I've seen schematics, is the AC4 just a slightly more progressive 
design ?


Thanx,
  Chuck, K1OM



--
Submissions:drakelist@www.zerobeat.net
Unsubscribe:[EMAIL PROTECTED] - unsubscribe 
drakelist in body

Hopelessly Lost:[EMAIL PROTECTED] - help in body of message
Zerobeat Web Page:  www.zerobeat.net - sponsored by www.tlchost.net
--





--
Submissions:drakelist@www.zerobeat.net
Unsubscribe:[EMAIL PROTECTED] - unsubscribe drakelist in body
Hopelessly Lost:[EMAIL PROTECTED] - help in body of message
Zerobeat Web Page:  www.zerobeat.net - sponsored by www.tlchost.net
--

Re: [drakelist] AC3 vs AC4 ?

[Garey Barrell]

Garey Barrell <[EMAIL PROTECTED]> made an utterance to the drakelist gang
--

73, Garey - K4OAH
Atlanta

Drake C-Line Service Manual




Ron Wagner wrote:



Ron Wagner <[EMAIL PROTECTED]> made an utterance to the drakelist gang
--
One big difference is that the AC3 has a set of resistors in the bias 
line.  Those resistors are jumper shorted out normally with a small 
screw. Lifting the jumper short allows you to easily measure the idle 
current (actually voltage across known resistance).  Much easier then 
trying to look at the fat needle against fat marking.


You can measure the current on the resistor under the chassis too, and 
should to make sure the finals are balanced.  But to set the current 
easily the AC3 was a gem.  IMHO.


Okay, something of a thesis.  :-)

73,
Ron


Visit my astronomy home page.   http://www.dma.org/~wagner
Amateur Radio Station: WD8SBB - Ron  and  KB8NRP - Joann


On Tue, 3 Jan 2006, Garey Barrell wrote:



Garey Barrell <[EMAIL PROTECTED]> made an utterance to the 
drakelist gang

--
Functionally identical.  Electrically "almost" identical.  Only real 
difference is the age of the components.


14 words, not counting the sig!

73, Garey - K4OAH
Atlanta

Drake C-Line Service Manual




chuck grandgent wrote:

chuck grandgent <[EMAIL PROTECTED]> made an utterance to the 
drakelist gang

--
OK, simple question.
In 25 words or less, what's the diff between AC3 and AC4 ?
I've seen schematics, is the AC4 just a slightly more progressive 
design ?


Thanx,
  Chuck, K1OM


--
Submissions:drakelist@www.zerobeat.net
Unsubscribe:[EMAIL PROTECTED] - unsubscribe drakelist in body
Hopelessly Lost:[EMAIL PROTECTED] - help in body of message
Zerobeat Web Page:  www.zerobeat.net - sponsored by www.tlchost.net
--

Re: [drakelist] AC3 vs AC4 ?

[Garey Barrell]

Garey Barrell <[EMAIL PROTECTED]> made an utterance to the drakelist gang
--
Ron -

That's true  I recall adding RCA jack "pigtails" to the connectors 
for my very early T-4X / AC-3 pair.  The AC-3 had a pigtail out of it's 
connector, but that was for the speaker connection for the TR-3/4.  Not 
needing that for my T-4X I moved it over to the VOX relay pin.


Also true that the VERY early AC-3s had a filter choke in the LV 
supply.  But I don't think there were that many of those sold.  I've 
only seen ONE aside from the one on your photo pages!


One other detail is that the AC-4 has a metal cover over the top of the 
chassis, while the AC-3 was open.


73, Garey - K4OAH
Atlanta

Drake C-Line Service Manual




Ron Baker wrote:


"Ron Baker" <[EMAIL PROTECTED]> made an utterance to the drakelist gang
--
The only real difference, the AC4 included the XMTR AGC & the VOX Relay
connectors mounted to the chassis, the AC3 did not have either one on the
chassis, electrically the rest was the same. 


Ron




chuck grandgent wrote:

 

chuck grandgent <[EMAIL PROTECTED]> made an utterance to the drakelist 
gang

--
OK, simple question.
In 25 words or less, what's the diff between AC3 and AC4 ?
I've seen schematics, is the AC4 just a slightly more progressive design ?

Thanx,
 Chuck, K1OM
   


--
Submissions:drakelist@www.zerobeat.net
Unsubscribe:[EMAIL PROTECTED] - unsubscribe drakelist in body
Hopelessly Lost:[EMAIL PROTECTED] - help in body of message
Zerobeat Web Page:  www.zerobeat.net - sponsored by www.tlchost.net
--

Re: [drakelist] AC3 vs AC4 ?

[Ron Wagner]

Ron Wagner <[EMAIL PROTECTED]> made an utterance to the drakelist gang
--
One big difference is that the AC3 has a set of resistors in the bias 
line.  Those resistors are jumper shorted out normally with a small screw. 
Lifting the jumper short allows you to easily measure the idle current 
(actually voltage across known resistance).  Much easier then trying to 
look at the fat needle against fat marking.


You can measure the current on the resistor under the chassis too, and 
should to make sure the finals are balanced.  But to set the current 
easily the AC3 was a gem.  IMHO.


Okay, something of a thesis.  :-)

73,
Ron


Visit my astronomy home page.   http://www.dma.org/~wagner
Amateur Radio Station: WD8SBB - Ron  and  KB8NRP - Joann


On Tue, 3 Jan 2006, Garey Barrell wrote:



Garey Barrell <[EMAIL PROTECTED]> made an utterance to the drakelist gang
--
Functionally identical.  Electrically "almost" identical.  Only real 
difference is the age of the components.


14 words, not counting the sig!

73, Garey - K4OAH
Atlanta

Drake C-Line Service Manual




chuck grandgent wrote:


chuck grandgent <[EMAIL PROTECTED]> made an utterance to the drakelist gang
--
OK, simple question.
In 25 words or less, what's the diff between AC3 and AC4 ?
I've seen schematics, is the AC4 just a slightly more progressive design ?

Thanx,
  Chuck, K1OM



--
Submissions:drakelist@www.zerobeat.net
Unsubscribe:[EMAIL PROTECTED] - unsubscribe drakelist in 
body

Hopelessly Lost:[EMAIL PROTECTED] - help in body of message
Zerobeat Web Page:  www.zerobeat.net - sponsored by www.tlchost.net
--


--
Submissions:drakelist@www.zerobeat.net
Unsubscribe:[EMAIL PROTECTED] - unsubscribe drakelist in body
Hopelessly Lost:[EMAIL PROTECTED] - help in body of message
Zerobeat Web Page:  www.zerobeat.net - sponsored by www.tlchost.net
--

RE: [drakelist] AC3 vs AC4 ?

[Ron Baker]

"Ron Baker" <[EMAIL PROTECTED]> made an utterance to the drakelist gang
--
The only real difference, the AC4 included the XMTR AGC & the VOX Relay
connectors mounted to the chassis, the AC3 did not have either one on the
chassis, electrically the rest was the same. 

Ron




chuck grandgent wrote:

>chuck grandgent <[EMAIL PROTECTED]> made an utterance to the drakelist 
>gang
>--
>OK, simple question.
>In 25 words or less, what's the diff between AC3 and AC4 ?
>I've seen schematics, is the AC4 just a slightly more progressive design ?
>
>Thanx,
>   Chuck, K1OM
>
>  
>
--
Submissions:drakelist@www.zerobeat.net
Unsubscribe:[EMAIL PROTECTED] - unsubscribe drakelist in
body
Hopelessly Lost:[EMAIL PROTECTED] - help in body of message
Zerobeat Web Page:  www.zerobeat.net - sponsored by www.tlchost.net
--

--
Submissions:drakelist@www.zerobeat.net
Unsubscribe:[EMAIL PROTECTED] - unsubscribe drakelist in body
Hopelessly Lost:[EMAIL PROTECTED] - help in body of message
Zerobeat Web Page:  www.zerobeat.net - sponsored by www.tlchost.net
--

RE: [drakelist] AC3 vs AC4 ?

[W7RY]

"W7RY" <[EMAIL PROTECTED]> made an utterance to the drakelist gang
--
Some of the very early  AC-3s had a choke input filter circuit. I don't
recall how many of those were made though.

73
Jim W7RY


-Original Message-
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] On Behalf Of chuck grandgent
Sent: Tuesday, January 03, 2006 5:19 PM
To: drakelist@www.zerobeat.net
Subject: [drakelist] AC3 vs AC4 ?


chuck grandgent <[EMAIL PROTECTED]> made an utterance to the drakelist
gang
--
OK, simple question.
In 25 words or less, what's the diff between AC3 and AC4 ?
I've seen schematics, is the AC4 just a slightly more progressive design
?

Thanx,
   Chuck, K1OM

--
Submissions:drakelist@www.zerobeat.net
Unsubscribe:[EMAIL PROTECTED] - unsubscribe drakelist
in body
Hopelessly Lost:[EMAIL PROTECTED] - help in body of message
Zerobeat Web Page:  www.zerobeat.net - sponsored by www.tlchost.net
--

--
Submissions:drakelist@www.zerobeat.net
Unsubscribe:[EMAIL PROTECTED] - unsubscribe drakelist in body
Hopelessly Lost:[EMAIL PROTECTED] - help in body of message
Zerobeat Web Page:  www.zerobeat.net - sponsored by www.tlchost.net
--

Re: [drakelist] AC3 vs AC4 ?

[Garey Barrell]

Garey Barrell <[EMAIL PROTECTED]> made an utterance to the drakelist gang
--
Functionally identical.  Electrically "almost" identical.  Only real 
difference is the age of the components.


14 words, not counting the sig!

73, Garey - K4OAH
Atlanta

Drake C-Line Service Manual




chuck grandgent wrote:


chuck grandgent <[EMAIL PROTECTED]> made an utterance to the drakelist gang
--
OK, simple question.
In 25 words or less, what's the diff between AC3 and AC4 ?
I've seen schematics, is the AC4 just a slightly more progressive design ?

Thanx,
  Chuck, K1OM

 


--
Submissions:drakelist@www.zerobeat.net
Unsubscribe:[EMAIL PROTECTED] - unsubscribe drakelist in body
Hopelessly Lost:[EMAIL PROTECTED] - help in body of message
Zerobeat Web Page:  www.zerobeat.net - sponsored by www.tlchost.net
--

[drakelist] AC3 vs AC4 ?

[chuck grandgent]

chuck grandgent <[EMAIL PROTECTED]> made an utterance to the drakelist gang
--
OK, simple question.
In 25 words or less, what's the diff between AC3 and AC4 ?
I've seen schematics, is the AC4 just a slightly more progressive design ?

Thanx,
   Chuck, K1OM

--
Submissions:drakelist@www.zerobeat.net
Unsubscribe:[EMAIL PROTECTED] - unsubscribe drakelist in body
Hopelessly Lost:[EMAIL PROTECTED] - help in body of message
Zerobeat Web Page:  www.zerobeat.net - sponsored by www.tlchost.net
--