Phil,
Re: the SPE-1K antenna autoswitching. Do you think there may be a concern
where you may see very transient high SWR back to the "hot" exciter finals
while the amp switches antenna input? There are some solid state tranceivers
whose RF finals might not like that too often. I know there has been some
discussions with the new IC-7800 having lots of final failures and antenna
switching with transient high SWR has been invoked as one potential reason.
73 Jerry
K1JOS
-----Original Message-----
>From: amps-request@contesting.com
>Sent: Jul 23, 2007 9:53 AM
>To: amps@contesting.com
>Subject: Amps Digest, Vol 55, Issue 52
>
>Send Amps mailing list submissions to
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>
>Today's Topics:
>
> 1. Solid state Vs Tube QRO (Phil & Debbie Salas)
> 2. Follow up on purchase from Paval. (robert briggs)
> 3. Looking for Clipperton L parts (John.)
> 4. AL-80B transformer tap (James M. Daly)
> 5. Re: AL-80B transformer tap (Gudguyham@aol.com)
> 6. Re: Solid state Vs Tube QRO (Roger)
> 7. Re: AL-80B transformer tap (James M. Daly)
> 8. Re: AL1500 PSU design (f6irf@free.fr)
> 9. Re: AL-80B transformer tap (Tom W8JI)
>
>
>----------------------------------------------------------------------
>
>Message: 1
>Date: Sun, 22 Jul 2007 20:28:28 -0500
>From: "Phil & Debbie Salas" <dpsalas@tx.rr.com>
>Subject: [Amps] Solid state Vs Tube QRO
>To: <amps@contesting.com>
>Message-ID: <000001c7ccc8$c5a5a040$0301a8c0@PhilSalas>
>Content-Type: text/plain; charset="us-ascii"
>
>You might also consider the SPE 1K-FA amp available from Array Solutions. I
>got to play with one for a couple of weeks, and it is pretty nice. It
>includes an internal auto-tuner and a 4-port antenna switch. You can
>connect it to two transceivers and it will picl the transceiver that is
>keyed and switch it to the antenna you've specified for this transceiver.
>It also has a sort of SO2R capability. I put a review of this amp on my
>website at www.ad5x.com <http://www.ad5x.com/> .
>
>
>
>Phil - AD5X
>
>
>
>------------------------------
>
>Message: 2
>Date: Mon, 23 Jul 2007 11:54:44 +1000
>From: "robert briggs" <vk3zl@bigpond.com>
>Subject: [Amps] Follow up on purchase from Paval.
>To: <amps@contesting.com>
>Message-ID: <005901c7cccc$716f6930$d7c628cb@your8abc512da0>
>Content-Type: text/plain; charset="iso-8859-1"
>
>Hi all.I am pleased to advise I received my Vacuum capacitor from Paval this
>morning.Beautifully packed.I would recommend Paval and Mats to anybody for
>good quick and honest dealing for those hard to find radio parts.
>
>Regards.....Bob VK3ZL..
>
>------------------------------
>
>Message: 3
>Date: Sun, 22 Jul 2007 21:28:20 -0500
>From: "John." <johne@tds.net>
>Subject: [Amps] Looking for Clipperton L parts
>To: amps@contesting.com
>Message-ID: <46A41244.9020509@tds.net>
>Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>
>Re building a Dentron Clipperton L and looking for some parts.
>
>Need a band switch or just the back switch section.
>
>Plate choke.
>
>1000PF 5KL door knob.
>
>572B tube's
>
>Any help with any of the parts would be nice.
>
>Thanks de John K?CQW
>
>
>
>------------------------------
>
>Message: 4
>Date: Sun, 22 Jul 2007 23:40:50 -0700 (PDT)
>From: "James M. Daly" <punk_itup@yahoo.com>
>Subject: [Amps] AL-80B transformer tap
>To: Amps@contesting.com
>Message-ID: <51571.72607.qm@web31604.mail.mud.yahoo.com>
>Content-Type: text/plain; charset=iso-8859-1
>
>Hey guys, I was pointed here by someone on the
>TowerTalk list, so if you are seeing this question for
>a second time please excuse me.
>
>Saturday night I install a new line voltage circuit in
>the radio room for use with my new Ameritron AL-80B
>amplifier.
>
>At that time I checked the new circuit with my DMM an
>"Ideal TestPro 361" (True RMS reading). At the
>receptacle on the wall the reading was 248VAC across
>the two hot legs, it was 1AM Sunday so there was no
>big demand on the neighborhood grid (rural, limited
>houses and few with air-conditioning, no businesses,
>and one HV line on a dead end street).
>
>Yesterday a little after noon on a Sunday I was
>reading 244VAC at the receptacle, obviously
>neighborhood demand was up compared to my early AM
>check.
>
>Now this morning, 2am Monday I am again reading
>248VAC.
>
>The AL-80B amplifier has taps for 240, 245, and
>250VAC. So the question is which one to select?
>Keeping in mind the local grid demands determining how
>much voltage potential will be presented to me, during
>the varied hours of my operation.
>
>1.) The 240VAC tap seems out because either way you
>will be hitting the amp with a 1.64% to 3.23% over
>voltage.
>2.) I am thinking that the 245VAC tap would be the
>choice to make; the line voltage might be a bit soft
>at times of high grid demand (0.4% under-voltage) but
>that is awful close, 1.20% over-voltage of the 248VAC
>potential during those late light hours on the low
>bands shouldn't hit the amplifier to hard.
>3.) The 250VAC tap also seems like a poor choice as
>either way the amp with a 2.46% to 0.80%
>under-voltage.
>
>So what do you guys think, is the 245VAC tap the way
>to go? Also keep in mind that I have only done three
>readings, the line voltage could drop closer to 240
>under further grid demand. It was suggested to me by
>KM1H to watch the effects on the tube filament
>voltage, but I do need a starting point, and I am
>quiet willing to admitt that I lack experience.
>
>Peace
>James - AD1L
>
>
>
>
>____________________________________________________________________________________
>Need a vacation? Get great deals
>to amazing places on Yahoo! Travel.
>http://travel.yahoo.com/
>
>
>------------------------------
>
>Message: 5
>Date: Mon, 23 Jul 2007 02:52:23 EDT
>From: Gudguyham@aol.com
>Subject: Re: [Amps] AL-80B transformer tap
>To: punk_itup@yahoo.com, Amps@contesting.com
>Message-ID: <cf6.146e7785.33d5aa27@aol.com>
>Content-Type: text/plain; charset="US-ASCII"
>
>
>In a message dated 7/23/2007 2:41:12 A.M. Eastern Daylight Time,
>punk_itup@yahoo.com writes:
>
>So what do you guys think, is the 245VAC tap the way
>to go? Also keep in mind that I have only done three
>readings, the line voltage could drop closer to 240
>under further grid demand. It was suggested to me by
>KM1H to watch the effects on the tube filament
>voltage, but I do need a starting point, and I am
>quiet willing to admit that I lack experience.
>
>Peace
>James - AD1L
>
>
>
>
>Hi James, You are VERY fortunate to have such "nice" line voltage. But to
>the point, the most important thing here is the filament voltage. You want
>your filament voltage to be 5 volts. Eimac will tolerate 5.25 volts, but you
>will get better tube life at 4.8 to 5 volts. The thing to do is to actually
>measure your filament voltage using the 245 tap and see what it is. If it's
>high go to the 250 tap. If it is spec, you can stay with 245 tap. The tube
>must be in the socket when measuring and measure right at the filament pins
>of the tube socket. As far as HV goes, any tap is OK for that. The lower
>the
>tap, the higher your plate voltage will be. You won't notice a difference
>of "on the air" signal but you will get a tad bit more power out on a lower
>tap. The filament voltage will dictate. 73 Lou
>
>
>
>************************************** Get a sneak peek of the all-new AOL at
>http://discover.aol.com/memed/aolcom30tour
>
>
>------------------------------
>
>Message: 6
>Date: Mon, 23 Jul 2007 03:56:56 -0400
>From: "Roger" <sub1@rogerhalstead.com>
>Subject: Re: [Amps] Solid state Vs Tube QRO
>To: "Phil & Debbie Salas" <dpsalas@tx.rr.com>, <amps@contesting.com>
>Message-ID: <001a01c7ccff$10741bc0$6400a8c0@shop32>
>Content-Type: text/plain; format=flowed; charset="iso-8859-1";
> reply-type=original
>
>
>
>
>> You might also consider the SPE 1K-FA amp available from Array Solutions.
>> I
>> got to play with one for a couple of weeks, and it is pretty nice. It
>> includes an internal auto-tuner and a 4-port antenna switch. You can
>> connect it to two transceivers and it will picl the transceiver that is
>
>The SPE K1-FA appears to be a bit more versatile with the multiple inputs
>and auto switched outputs and it appears to have good specs with about the
>same or a tad more output than the HL-1.5KFX, but the Tokyo amp appears to
>have a much more professional look to the construction. Add to that the
>price of the auto tuner which is built into the SPE K1FA and the HL-1.5KFX
>comes out a bit more expensive although only by about $200 USD. It also
>appears the SPE amp is a bit more automated and depends less on the controls
>of the transmitter for auto band switching and antenna selection. Neither
>have much of a range for the auto tuning and I'd still need my old tuner for
>at least 160 and probably for all of the antennas on 75 as well.
>
>If it wasn't for the mechanical appearance the SPE amp would be a hands down
>choice, but I tend to link the finish with the thought that went into the
>design of the amp.
>
>Thanks for the link and information.
>
>73
>
>Roger (K8RI)
>> keyed and switch it to the antenna you've specified for this transceiver.
>> It also has a sort of SO2R capability. I put a review of this amp on my
>> website at www.ad5x.com <http://www.ad5x.com/> .
>>
>>
>>
>> Phil - AD5X
>>
>> _______________________________________________
>> Amps mailing list
>> Amps@contesting.com
>> http://lists.contesting.com/mailman/listinfo/amps
>
>
>
>------------------------------
>
>Message: 7
>Date: Mon, 23 Jul 2007 04:56:45 -0400
>From: "James M. Daly" <AD1L@AD1L.COM>
>Subject: Re: [Amps] AL-80B transformer tap
>To: <amps@contesting.com>
>Message-ID: <002201c7cd07$67f51a90$0200a8c0@jmd>
>Content-Type: text/plain; charset="US-ASCII"
>
>Lou,
>Thank you for your reply. Ok, so I am going to start with the 245VAC tap. I
>will then search the list archives for the proper procedure for measuring
>the filament voltage after that... remember complete newbie to tube amps
>here (built a couple bricks in the past).
>
>Peace
>James - AD1L
>
>
>--- Gudguyham wrote:
>
>> Hi James, You are VERY fortunate to have such
>> "nice" line voltage. But to
>> the point, the most important thing here is the
>> filament voltage. You want
>> your filament voltage to be 5 volts. Eimac will
>> tolerate 5.25 volts, but you
>> will get better tube life at 4.8 to 5 volts. The
>> thing to do is to actually
>> measure your filament voltage using the 245 tap and
>> see what it is. If it's
>> high go to the 250 tap. If it is spec, you can
>> stay with 245 tap. The tube
>> must be in the socket when measuring and measure
>> right at the filament pins
>> of the tube socket. As far as HV goes, any tap is
>> OK for that. The lower the
>> tap, the higher your plate voltage will be. You
>> won't notice a difference
>> of "on the air" signal but you will get a tad bit
>> more power out on a lower
>> tap. The filament voltage will dictate. 73 Lou
>
>
>
>
>------------------------------
>
>Message: 8
>Date: Mon, 23 Jul 2007 12:15:37 +0200
>From: f6irf@free.fr
>Subject: Re: [Amps] AL1500 PSU design
>To: amps@contesting.com
>Message-ID: <1185185737.46a47fc9de1e3@imp.free.fr>
>Content-Type: text/plain; charset=ISO-8859-1
>
>Just as a conclusion of my previous posts:
>- Replaced all diodes and capacitors on the rectifier board (used BY255, and
>new
>2kV ceramic disk capacitors)
>- Installed a new capacitor board made of 12x 330uF / 400V and 100k resistors.
>- replaced the 10ohms original "starting" resistor, by 2 "sfernice" 4.7 ohms
>/10w
>
>No "bang" this time, everything is working fine:
>- So, in case of similar unfortune (*), it might be advisable to replace all
>components on the rectifier board, not just the burned diodes (like I did on
>the
>first repair attempt).
>- Of course the caps discharge time is a bit longer than on the initial design,
>but still OK as it is practicaly impossible to remove all screws before the HV
>has reached 0...
>
>(*) As a reminder the amp was unused since 2002, and the PSU blew up at first
>power on, probably due to a defective electrolytic capacitor.
>
>Patrick
>
>
>
>
>
>
>Re: [Amps] AL1500 PSU design
>from [f6irf] [Permanent Link][Original]
>
>To: Tom W8JI <w8ji@w8ji.com>
>Subject: Re: [Amps] AL1500 PSU design
>From: f6irf@free.fr
>Date: Thu, 14 Jun 2007 09:35:33 +0200
>List-post: <mailto:amps@contesting.com>
>
>> Someone asked if you could be putting 240V on a 120 winding
>> through a wiring error, and indeed you could be doing that.
>
>Tom,
>The first thing I did after the first bang was to check the transformer. I
>found
>that it was wired for 220V, I rewired it for 240V according to the manual
>indications (I have around 235V +/-5V at home), and checked the transformer
>alone using a HV-probe 1st (*), then a voltage divider made of 4x1Mohm
>resistors. The AC voltage was found conform to the expectations (around 2320V
>AC- if I remember correctly, with the primary wired for 240V - of course
>subject
>to resistance tolerance)- that should make around 3280 DC without load - isn' t
>it? And of course I checked more than twice that the wiring was conform to the
>manual indications...
>
>(*) the HV probe is a 1/1000 commercial model; associated with a digital
>multimeter, it measures correctly the mains value, but while connected to the
>transformer secondary, it was giving highly fluctuating indications - I guess
>due to the important magnetic field around the transformer. It is why I tried
>with the voltage divider and an analog multimeter (40,000ohm/V - 1500V AC) my
>digital multimeter being limited to 500V AC.
>
>
>
>
>
>
>Quoting Tom W8JI <w8ji@w8ji.com>:
>
>> Patrick
>>
>> Someone asked if you could be putting 240V on a 120 winding
>> through a wiring error, and indeed you could be doing that.
>>
>> That was a good suggestion!
>>
>> Be sure you do not have a wiring error that is applying too
>> much voltage since the dual primary has two 120V windings,
>> one with a 100V tap.
>>
>> 73 Tom
>>
>>
>>
>
>
>_______________________________________________
>Amps mailing list
>Amps@contesting.com
>http://lists.contesting.com/mailman/listinfo/amps
>
>
>
>
>
>
>
>------------------------------
>
>Message: 9
>Date: Mon, 23 Jul 2007 09:53:25 -0400
>From: "Tom W8JI" <w8ji@w8ji.com>
>Subject: Re: [Amps] AL-80B transformer tap
>To: "James M. Daly" <punk_itup@yahoo.com>, <Amps@contesting.com>
>Message-ID: <015601c7cd30$e583c190$640fa8c0@radioroom>
>Content-Type: text/plain; format=flowed; charset="iso-8859-1";
> reply-type=original
>
>> 1.) The 240VAC tap seems out because either way you
>> will be hitting the amp with a 1.64% to 3.23% over
>> voltage.
>> 2.) I am thinking that the 245VAC tap would be the
>> choice to make; the line voltage might be a bit soft
>> at times of high grid demand (0.4% under-voltage) but
>> that is awful close, 1.20% over-voltage of the 248VAC
>> potential during those late light hours on the low
>> bands shouldn't hit the amplifier to hard.
>> 3.) The 250VAC tap also seems like a poor choice as
>> either way the amp with a 2.46% to 0.80%
>> under-voltage.
>
>Jim,
>
>I picked the transformer windings in the AL80 series of
>amplifiers (and all Ameritron amps) other than the original
>AL80 below S/N 300.
>
>Here are the facts:
>
>People are WAY too overboard about filament voltage. The
>reason is they like to apply what is important to a 24 hour
>365 day a year commercial operation to Ham radio.
>
>With a BC station the tube is normally operated at a small
>fraction of rated dissipation, anode and screen voltages,
>dissipation, and emission currents. The filament and tube is
>on and hot, and it almost never cycles. Since there is no
>real thermal stress and the tube is loafing along at a
>fraction of rated emission and dissipation, emission life
>can be an important parameter.
>
>With Ham radio, people complain about noise. They complain
>about price. They complain about size. They also turn the
>gear off and on (sometimes several times a day). The tube is
>run at or beyond CCS limits, the airflow is at or near the
>minimum value, and everything goes through big thermal
>cycles. Many tubes are also not made as well as they once
>were so far as seal quality and pumping down of the tubes.
>The materials inside tubes are sometimes not as good.
>
>Because of that, Ham radio applications are MUCH different.
>You will virtually NEVER find a low emission tube in amateur
>service compared to other failures like overdissipation,
>bent or warped elements from handling or thermal cycling, or
>tube manufacturing defects like seal leakage or outgassing
>of materials inside the tube.
>
>Like the tank Q of 12, some people just get way too dramatic
>about making something that is down in the noise floor be
>some *exact* value, and they often don't even understand why
>they are using a certain number. For example, did you know
>the voltage of transformers drops as they heat? How many
>people caution you to set the operating voltage with a fully
>warm transformer or filament choke?
>
>The real truth is if the voltage on your 3-500Z is between 5
>or 5.25 volts, or even if it is a little high, it won't make
>a bit of difference in the life of the tube if you lower it
>to some magical number. You won't see 10,000 operating hours
>in amateur service, and you almost certainly won't have a
>tube that fails because of low emission unless you run the
>thing at 6 volts. If you keep the voltage somewhere near 5
>volts it will be like 99% of all the other tubes that fail
>and dies from something you really can't control.
>
>The main reason you have taps on that transformer is to set
>the HV. The bandswitch and tuning cap, because of cost
>necessity in the Ham market, don't have a lot of headroom.
>The most damaging thing is to let the HV get too high, so
>the taps allow you to keep the HV at a reasonable value not
>exceeding a safe margin.
>
>The filament, if you watch the HV and follow guidelines,
>will be right in the ballpark. This is why the manual tells
>you to set the tap to the next HIGHER voltage UP from the
>maximum voltage you expect to see.
>
>You can measure the filament voltage and do whatever you
>like (it's your amp), but the REAL common cause of problems
>is letting the HV become higher than normal and the way you
>prevent that is to follow the manual and set the line taps
>on the transformer to the closest setting HIGHER than the
>maximum expected voltage.
>
>73 Tom
>
>
>
>
>------------------------------
>
>_______________________________________________
>Amps mailing list
>Amps@contesting.com
>http://lists.contesting.com/mailman/listinfo/amps
>
>
>End of Amps Digest, Vol 55, Issue 52
>************************************
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