[1000mp] RE: 1000mp Digest, Vol 19, Issue 23
D. J.
dalej2 at mac.com
Tue Nov 29 21:55:07 EST 2005
You have no concern with your MP other than in RTTY or other high
duty cycle modes to turn your power down 50 percent per Yaesu. The
Yaesu radios are not 100 percent duty cycle. Ok with CW and SSB at
100 w.
Class A operation is only on the MKV and field. While class A is a
good idea, that mode is very inefficent and uses a lot of power. I
never use the class A mode here.
Dale
On 29, Nov 2005, at 20:37, Fred Lowell wrote:
> Hi all,
>
> Pardon my ignorance, but is the "Very Hot Final Heatsinks" issue a
> concern
> for those of us with the basic FT-1000MP (no MK V and no Field)? I am
> unfamiliar with Class A. Anyone who could enlighten me would be
> appreciated.
>
> Thanks and 73,
>
> Fred N7PZ
>
> -----Original Message-----
> From: 1000mp-bounces at mailman.qth.net [mailto:1000mp-
> bounces at mailman.qth.net]
> On Behalf Of 1000mp-request at mailman.qth.net
> Sent: Tuesday, November 29, 2005 6:22 PM
> To: 1000mp at mailman.qth.net
> Subject: 1000mp Digest, Vol 19, Issue 23
>
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> Today's Topics:
>
> 1. Re: Very Hot Final Heatsinks (Rob Atkinson)
> 2. RE: Very Hot Final Heatsinks (Adam Farson)
> 3. Re: Very Hot Final Heatsinks (Hans Remeeus)
> 4. Re: Very Hot Final Heatsinks (Rick Moskovits)
> 5. Re: Very Hot Final Heatsinks (Hans Remeeus)
> 6. Wanted: Late MarkV Field (John L Merrill)
> 7. More listening audio and other stuff (Cqtestk4xs at aol.com)
> 8. RE: More listening audio and other stuff (Garry Shapiro)
> 9. Re: More listening audio and other stuff (D. J.)
> 10. RE: More listening audio and other stuff (Joe Subich, W4TV)
>
>
> ----------------------------------------------------------------------
>
> Message: 1
> Date: Tue, 29 Nov 2005 08:33:20 -0600
> From: Rob Atkinson <k5uj at sbcglobal.net>
> Subject: Re: [1000mp] Very Hot Final Heatsinks
> To: All about Yaesu 1000mp <1000mp at mailman.qth.net>
> Message-ID: <169C53EC-60E5-11DA-A936-0003936E0A3C at sbcglobal.net>
> Content-Type: text/plain; charset=US-ASCII; format=flowed
>
> i stay out of class A entirely. i heard a new PA costs $700 in the
> u.s. for the 200 w. version. i almost fried mine anyway one time
> when i put the cover back on and the speaker leads obstructed the fan
> and kept it from turning. just by luck i touched the heat sink after
> about 15 or 20 minutes and was it ever hot! pulled the cover off and
> saw the speaker wires down in the fan. after that close call, plus
> hearing over the past year or so, all the stories about class A doing
> in the PA, I stay on AB. If in AB ur heat sink still gets too hot,
> I'd just aim a second (external) fan down on it.
>
> with the increased popularity of high duty cycle modes, plus a renewed
> interest in AM, the finals on rigs are getting a workout they did not
> receive back in the days when a transceiver was made to do ssb and cw.
> i wish manufacturers could make the new rigs more like ccs
> transmitters,
> but i guess the cost would by sky high.
>
> rob / k5uj
>
>
>
> On Monday, November 28, 2005, at 03:16 PM, Hans Remeeus wrote:
>
>>
>> Class-A uses a constant current. This constant current is important
>> for a lower TX distortion. When you decrease the power output from 75
>> to e.g. 25 Watts this has to be absorbed by the heat sink. So the
>> heatsink has two jobs: handle the constant (HIGH) current and handle
>> the absorbtions of the 50 Watts in less power output. This is too
>> much
>> for the finals. When an amplifier is operated in Class A, it will be
>> hottest at zero output power, because all of the DC power input will
>> be converted to heat.
>>
>> This is the main reason why I sold my Mark-V 200 and bought the
>> Mark-V
>> Field with 25 Watts Class-A, which is a very good power input for my
>> linear amplifier Acom 2000A. It then gives 800 Watt power output,
>> which in most situations is more than enough.
>>
>> To be honest; who ever will notice that you are transmitting in
>> Class-A instead of Class-AB...? IMHO Class-A is nice to have, but not
>> need to have.
>>
>> 73,
>> Hans Remeeus (PA1HR)
>> http://www.remeeus.nl
>> Communication is about people, the rest is technology.
>>
>>
>>
>>
>> William Shadid schreef:
>>> Norm,
>>>
>>> Hans is correct. I long ago learned this with my Mark V -- leave the
>>> power level at maximum on Class A. I note a higher temperature level
>>> in Class A but nothing like what I hear about on the reflectors. Up
>>> to now I had thought this to be a problem with selected radios --
>>> but
>>> Hans' note gets me to thinking that it is really a lack of
>>> understanding with the radio.
>>> Yaesu
>>> should be more clear about this -- but they certainly do not have an
>>> edge on things omitted from the manual!!
>>>
>>> I drive an older Drake L-7 with my Mark V and use the Class A
>>> selection simply to keep my drive power low. I do not use Class A
>>> when I run PSK.
>>> While I don't often run the amplifier, I can say that I note only
>>> somewhat higher heat sink temperatures. The fins are far cooler than
>>> running older domestic, solid state radios such as an old Cubic
>>> Astro
>>> 103 with its large rear heat sink. They are also much cooler than
>>> the
>>> single heat sink on my Ten-Tec Omni VI+ after a long operating
>>> session. If you are experiencing "scalding" temperatures at 75 watts
>>> output, Class A, I would say that a call to Yaesu is in order.
>>>
>>> 73,
>>>
>>> -Bill, WA9MXQ
>>>
>> ______________________________________________________________
>> 1000mp mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/1000mp
>> Help: http://mailman.qth.net/mmfaq.html
>> Post: mailto:1000mp at mailman.qth.net
>>
>
>
>
> ------------------------------
>
> Message: 2
> Date: Tue, 29 Nov 2005 10:44:59 -0800
> From: Adam Farson <farson at shaw.ca>
> Subject: RE: [1000mp] Very Hot Final Heatsinks
> To: 'All about Yaesu 1000mp' <1000mp at mailman.qth.net>
> Message-ID: <002001c5f515$00a0be60$0300005a at max>
> Content-Type: text/plain; charset=us-ascii
>
> Hi Rob,
>
> Actually, in terms of the potential reduction in transmitted system
> IMD
> (when using SSB), I do not believe that Class A operation of the
> exciter is
> worth the risk involved.
>
> http://www.qsl.net/ab4oj/icom/ic756pro_notes.html#imd
>
> Cheers for now, 73,
> Adam VA7OJ/AB4OJ
>
>
>
>
> Scanned for viruses by Blue Coat
> http://www.WinProxy.com/
>
>
> ------------------------------
>
> Message: 3
> Date: Tue, 29 Nov 2005 21:02:56 +0100
> From: Hans Remeeus <hans at remeeus.nl>
> Subject: Re: [1000mp] Very Hot Final Heatsinks
> To: All about Yaesu 1000mp <1000mp at mailman.qth.net>
> Message-ID: <438CB3F0.2060404 at remeeus.nl>
> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>
> The Class-A is a very nice marketing instrument to up-value the
> Mark-V.
> I don't think this was necessary, as the price/quality-relation of the
> Mark-V is one of the highest on the market.
>
> If Class-A really should be a 'need-to-have' feature, then other
> brands
> would have implemented this in their rigs as well. They did'nt...
>
> Reducing the power will not cause any problem while running Class-
> AB on the
> Mark-V .
>
> When driving Class-A; always do this at the highest power output!
> Never
> reduce power. Yaesu should have writting this as warning in the
> operating
> manuals of the Mark-V series.
>
> 73,
> Hans Remeeus (PA1HR)
> http://www.remeeus.nl
> Communication is about people, the rest is technology.
>
>
>
>
> Rob Atkinson schreef:
>> i stay out of class A entirely. i heard a new PA costs $700 in the
>> u.s. for the 200 w. version. i almost fried mine anyway one time
>> when i put the cover back on and the speaker leads obstructed the fan
>> and kept it from turning. just by luck i touched the heat sink
>> after
>> about 15 or 20 minutes and was it ever hot! pulled the cover off
>> and
>> saw the speaker wires down in the fan. after that close call, plus
>> hearing over the past year or so, all the stories about class A doing
>> in the PA, I stay on AB. If in AB ur heat sink still gets too hot,
>> I'd just aim a second (external) fan down on it.
>>
>> with the increased popularity of high duty cycle modes, plus a
>> renewed
>> interest in AM, the finals on rigs are getting a workout they did not
>> receive back in the days when a transceiver was made to do ssb and
>> cw. i wish manufacturers could make the new rigs more like ccs
>> transmitters, but i guess the cost would by sky high.
>>
>> rob / k5uj
>>
>>
>>
>> On Monday, November 28, 2005, at 03:16 PM, Hans Remeeus wrote:
>>
>>>
>>> Class-A uses a constant current. This constant current is important
>>> for a lower TX distortion. When you decrease the power output
>>> from 75
>>> to e.g. 25 Watts this has to be absorbed by the heat sink. So the
>>> heatsink has two jobs: handle the constant (HIGH) current and handle
>>> the absorbtions of the 50 Watts in less power output. This is too
>>> much for the finals. When an amplifier is operated in Class A, it
>>> will be hottest at zero output power, because all of the DC power
>>> input will be converted to heat.
>>>
>>> This is the main reason why I sold my Mark-V 200 and bought the
>>> Mark-V Field with 25 Watts Class-A, which is a very good power input
>>> for my linear amplifier Acom 2000A. It then gives 800 Watt power
>>> output, which in most situations is more than enough.
>>>
>>> To be honest; who ever will notice that you are transmitting in
>>> Class-A instead of Class-AB...? IMHO Class-A is nice to have, but
>>> not
>>> need to have.
>>>
>>> 73,
>>> Hans Remeeus (PA1HR)
>>> http://www.remeeus.nl
>>> Communication is about people, the rest is technology.
>>>
>>>
>>>
>>>
>>> William Shadid schreef:
>>>> Norm,
>>>>
>>>> Hans is correct. I long ago learned this with my Mark V -- leave
>>>> the
>>>> power level at maximum on Class A. I note a higher temperature
>>>> level
>>>> in Class A but nothing like what I hear about on the reflectors. Up
>>>> to now I had thought this to be a problem with selected radios --
>>>> but Hans' note gets me to thinking that it is really a lack of
>>>> understanding with the radio. Yaesu should be more clear about this
>>>> -- but they certainly do not have an edge on things omitted from
>>>> the
>>>> manual!!
>>>>
>>>> I drive an older Drake L-7 with my Mark V and use the Class A
>>>> selection simply to keep my drive power low. I do not use Class
>>>> A when I
> run PSK.
>>>> While I don't often run the amplifier, I can say that I note only
>>>> somewhat higher heat sink temperatures. The fins are far cooler
>>>> than
>>>> running older domestic, solid state radios such as an old Cubic
>>>> Astro 103 with its large rear heat sink. They are also much cooler
>>>> than the single heat sink on my Ten-Tec Omni VI+ after a long
>>>> operating session. If you are experiencing "scalding" temperatures
>>>> at 75 watts output, Class A, I would say that a call to Yaesu is in
>>>> order.
>>>>
>>>> 73,
>>>>
>>>> -Bill, WA9MXQ
>>>>
>>> ______________________________________________________________
>>> 1000mp mailing list
>>> Home: http://mailman.qth.net/mailman/listinfo/1000mp
>>> Help: http://mailman.qth.net/mmfaq.html
>>> Post: mailto:1000mp at mailman.qth.net
>>>
>>
>> ______________________________________________________________
>> 1000mp mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/1000mp
>> Help: http://mailman.qth.net/mmfaq.html
>> Post: mailto:1000mp at mailman.qth.net
>>
>
>
> ------------------------------
>
> Message: 4
> Date: Tue, 29 Nov 2005 16:47:14 -0400
> From: Rick Moskovits <rick.moskovits at ns.sympatico.ca>
> Subject: Re: [1000mp] Very Hot Final Heatsinks
> To: hans at remeeus.nl, All about Yaesu 1000mp <1000mp at mailman.qth.net>
> Message-ID: <438CBE52.14232232 at ns.sympatico.ca>
> Content-Type: text/plain; charset=us-ascii
>
> Hans, can the mkv field be operated in class A safley?- I have not
> done this
> and now i am quite concerned- any help with your experience on this
> would be
> most appreciated!
> vy 73, Rick-VE1RNM
>
> Hans Remeeus wrote:
>
>> Class-A uses a constant current. This constant current is important
>> for a lower TX distortion. When you decrease the power output from 75
>> to e.g. 25 Watts this has to be absorbed by the heat sink. So the
>> heatsink has two jobs: handle the constant (HIGH) current and handle
>> the absorbtions of the 50 Watts in less power output. This is too
>> much
>> for the finals. When an amplifier is operated in Class A, it will be
>> hottest at zero output power, because all of the DC power input will
>> be converted to heat.
>>
>> This is the main reason why I sold my Mark-V 200 and bought the
>> Mark-V
>> Field with 25 Watts Class-A, which is a very good power input for my
>> linear amplifier Acom 2000A. It then gives 800 Watt power output,
>> which in most situations is more than enough.
>>
>> To be honest; who ever will notice that you are transmitting in
>> Class-A instead of Class-AB...? IMHO Class-A is nice to have, but
>> not need
> to have.
>>
>> 73,
>> Hans Remeeus (PA1HR)
>> http://www.remeeus.nl
>> Communication is about people, the rest is technology.
>>
>> William Shadid schreef:
>>> Norm,
>>>
>>> Hans is correct. I long ago learned this with my Mark V -- leave the
>>> power level at maximum on Class A. I note a higher temperature level
>>> in Class A but nothing like what I hear about on the reflectors. Up
>>> to now I had thought this to be a problem with selected radios --
>>> but Hans' note gets me to thinking that it is really a lack of
>>> understanding with the radio.
>>> Yaesu
>>> should be more clear about this -- but they certainly do not have an
>>> edge on things omitted from the manual!!
>>>
>>> I drive an older Drake L-7 with my Mark V and use the Class A
>>> selection simply to keep my drive power low. I do not use Class A
>>> when I
> run PSK.
>>> While I don't often run the amplifier, I can say that I note only
>>> somewhat higher heat sink temperatures. The fins are far cooler than
>>> running older domestic, solid state radios such as an old Cubic
>>> Astro 103 with its large rear heat sink. They are also much cooler
>>> than the single heat sink on my Ten-Tec Omni VI+ after a long
>>> operating session. If you are experiencing "scalding" temperatures
>>> at 75 watts output, Class A, I would say that a call to Yaesu is in
>>> order.
>>>
>>> 73,
>>>
>>> -Bill, WA9MXQ
>>>
>> ______________________________________________________________
>> 1000mp mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/1000mp
>> Help: http://mailman.qth.net/mmfaq.html
>> Post: mailto:1000mp at mailman.qth.net
>
>
>
>
> ------------------------------
>
> Message: 5
> Date: Tue, 29 Nov 2005 22:45:38 +0100
> From: Hans Remeeus <hans at remeeus.nl>
> Subject: Re: [1000mp] Very Hot Final Heatsinks
> Cc: All about Yaesu 1000mp <1000mp at mailman.qth.net>
> Message-ID: <438CCC02.4080706 at remeeus.nl>
> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>
> Hello Rick,
>
> Yes, it can. Make short transmissions. And don't reduce the power
> output!
>
> E.g. I use Class-A during SSB-transmissions with the Mark-V Field
> on the
> maximum 25 Watt power output, to drive the Acom 2000A linear
> amplifier.
> But not during contests or other longer periods of operation.
>
> And always keep an eye on the air coming from the PA.
>
> 73,
> Hans Remeeus (PA1HR)
> http://www.remeeus.nl
> Communication is about people, the rest is technology.
>
>
>
> Rick Moskovits schreef:
>> Hans, can the mkv field be operated in class A safley?- I have not
>> done this and now i am quite concerned- any help with your experience
>> on this would be most appreciated!
>> vy 73, Rick-VE1RNM
>>
>
>
>
> ------------------------------
>
> Message: 6
> Date: Tue, 29 Nov 2005 19:10:15 -0500
> From: "John L Merrill" <jmerrill1 at adelphia.net>
> Subject: [1000mp] Wanted: Late MarkV Field
> To: "1000mp" <1000mp at mailman.qth.net>
> Message-ID: <000001c5f542$7117f7d0$6601a8c0 at WIVB>
> Content-Type: text/plain; charset="us-ascii"
>
> Looking for a late Mark V Field with serial number starting with 3
> or 4 or
> higher.
>
> Please reply direct off list.
>
> 73,
> John N1JM
>
>
>
> ------------------------------
>
> Message: 7
> Date: Tue, 29 Nov 2005 20:07:03 EST
> From: Cqtestk4xs at aol.com
> Subject: [1000mp] More listening audio and other stuff
> To: 1000mp at mailman.qth.net
> Message-ID: <289.d60b92.30be5537 at aol.com>
> Content-Type: text/plain; charset="US-ASCII"
>
> I love my Mark V, but I wish there was a way to get more audio to the
> headphones. I like to keep the RF gain turned back since it
> "quiets" the
> band, but the rx does not have sufficient audio to pull the weak
> ones out if
> I do that.
> Any suggestions?
>
> Second, any way to, when running, make the second rx as narrow as
> the first
> one so I can S/P with it on the same band in contests?
>
> Bill K4XS
>
>
> ------------------------------
>
> Message: 8
> Date: Tue, 29 Nov 2005 17:41:38 -0800
> From: "Garry Shapiro" <garry at ni6t.com>
> Subject: RE: [1000mp] More listening audio and other stuff
> To: "All about Yaesu 1000mp" <1000mp at mailman.qth.net>
> Message-ID: <NNEMILONANDNONJJNADBEELCEMAA.garry at ni6t.com>
> Content-Type: text/plain; charset="us-ascii"
>
> Yaesu has a fix involving swapping out some SM resistors to
> increase gain in
> the audio output amplifiers.
>
> -----Original Message-----
> From: 1000mp-bounces at mailman.qth.net
> [mailto:1000mp-bounces at mailman.qth.net]On Behalf Of Cqtestk4xs at aol.com
> Sent: Tuesday, November 29, 2005 5:07 PM
> To: 1000mp at mailman.qth.net
> Subject: [1000mp] More listening audio and other stuff
>
>
> I love my Mark V, but I wish there was a way to get more audio to the
> headphones. I like to keep the RF gain turned back since it
> "quiets" the
> band, but the rx does not have sufficient audio to pull the weak
> ones out if
> I do that.
> Any suggestions?
>
> Second, any way to, when running, make the second rx as narrow as
> the first
> one so I can S/P with it on the same band in contests?
>
> Bill K4XS
> ______________________________________________________________
> 1000mp mailing list
> Home: http://mailman.qth.net/mailman/listinfo/1000mp
> Help: http://mailman.qth.net/mmfaq.html
> Post: mailto:1000mp at mailman.qth.net
>
>
>
> ------------------------------
>
> Message: 9
> Date: Tue, 29 Nov 2005 19:47:23 -0600
> From: "D. J." <dalej2 at mac.com>
> Subject: Re: [1000mp] More listening audio and other stuff
> To: All about Yaesu 1000mp <1000mp at mailman.qth.net>
> Message-ID: <1A400DB8-5AE1-4157-8AD6-A17C30136E36 at mac.com>
> Content-Type: text/plain; charset=US-ASCII; delsp=yes; format=flowed
>
> Did you turn up the headphone gain pots? They are in the little
> panel on
> top of the radio.
>
> Dale
>
>
> On 29, Nov 2005, at 19:07, Cqtestk4xs at aol.com wrote:
>
>> I love my Mark V, but I wish there was a way to get more audio to the
>> headphones. I like to keep the RF gain turned back since it "quiets"
>> the band, but the rx does not have sufficient audio to pull the weak
>> ones out if I do that.
>> Any suggestions?
>>
>> Second, any way to, when running, make the second rx as narrow as the
>> first one so I can S/P with it on the same band in contests?
>>
>> Bill K4XS
>> ______________________________________________________________
>> 1000mp mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/1000mp
>> Help: http://mailman.qth.net/mmfaq.html
>> Post: mailto:1000mp at mailman.qth.net
>
>
>
> ------------------------------
>
> Message: 10
> Date: Tue, 29 Nov 2005 21:20:43 -0500
> From: "Joe Subich, W4TV" <k4ik at subich.com>
> Subject: RE: [1000mp] More listening audio and other stuff
> To: "'All about Yaesu 1000mp'" <1000mp at mailman.qth.net>,
> <Cqtestk4xs at aol.com>
> Message-ID: <008001c5f554$aa9f6d00$c080a8c0 at laptop>
> Content-Type: text/plain; charset="us-ascii"
>
>
> Bill,
>
>> Second, any way to, when running, make the second rx as narrow as the
>> first one so I can S/P with it on the same band in contests?
>
> The second receiver is double conversion vs. triple conversion for
> the main
> receiver. You can install one CW filter in the second receiver ...
> it is
> selected by pressing "sub" followed by NAR1 or NAR2. This must be
> done once
> per band.
>
> After replacing the 500 Hz Collins mechanical filter in my second
> receiver
> with an INRAD 721-C (500 Hz crystal), I heartily recommend either
> the 721-C,
> a 703-C (400 Hz) or a Yaesu YF-110C (the old 500 Hz crystal filter
> from a
> FT-1000D if you can find one). The crystal filter made the second
> receiver
> much more usable.
>
> If you are talking about tightening up the SSB performance, it is
> possible
> to "wire in" an INRAD 702 (2.1 KHz) in place of the Murata 6 pole
> 2.4 KHz
> ceramic filter. The filter will not fit in the available space ...
> it must
> be located elsewhere and connected by small coax (RG-174).
>
> 73,
>
> ... Joe, W4TV
>
>
> ------------------------------
>
> ______________________________________________________________
> 1000mp mailing list
> Home: http://mailman.qth.net/mailman/listinfo/1000mp
> Help: http://mailman.qth.net/mmfaq.html
> Post: mailto:1000mp at mailman.qth.net
>
>
> End of 1000mp Digest, Vol 19, Issue 23
> **************************************
>
> ______________________________________________________________
> 1000mp mailing list
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