Had a similar problem and after removing the label, I found the ground side
of the loop unsoldered. Resoldered it, that fixed it......Bruce W1GBS
----- Original Message -----
From: <amps-request@contesting.com>
To: <amps@contesting.com>
Sent: Sunday, April 17, 2005 11:53 AM
Subject: Amps Digest, Vol 28, Issue 43
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> Today's Topics:
>
> 1. Re: article in Nature, modified Aurora via HF tspa
> (G3rzp@aol.com)
> 2. Re: fl2100b part 3 (G3rzp@aol.com)
> 3. Re: article in Nature, modified Aurora via HF tspa
> (G3rzp@aol.com)
> 4. Re: fl2100b part 3 (Mike Sawyer)
> 5. Re: Intermittent Bird element (Will Matney)
> 6. Re: Intermittent Bird element (Paul Higginson)
> 7. Re: article in Nature, modified Aurora via HF tspa
> (R.Measures)
> 8. grid dip meters (John Irwin)
> 9. Re: Intermittent Bird element (Will Matney)
> 10. Re: grid dip meters (Will Matney)
>
>
> ----------------------------------------------------------------------
>
> Message: 1
> Date: Sun, 17 Apr 2005 05:29:49 EDT
> From: G3rzp@aol.com
> Subject: Re: [Amps] article in Nature, modified Aurora via HF
> tspa
> To: garyschafer@comcast.net, n3ji@yahoo.com
> Cc: amps@contesting.com
> Message-ID: <13c.11790916.2f93868d@aol.com>
> Content-Type: text/plain; charset="US-ASCII"
>
>
> In a message dated 16/04/2005 21:18:09 GMT Standard Time,
> garyschafer@comcast.net writes:
>
> But you must be able to disable the agc or it won't work.
>
>
>
> You must also make sure that the receiver audio dynamic range is
> sufficient.
> F'r instance, if the the AF output is set to 50mW without the amp, it
> must
> do at elast 500mW without gain compression when the amp is on - if the
> amp
> gives 10dB of gain. If it gives 20dB, then you need an uncompressed AF
> output
> capability of 5 watts.
>
> Once had to deal with an applications complaint from a professional (?)
> lab
> where they made that mistake when trying to measure sensitivity.
>
> 73
>
> Peter G3RZP
>
>
> ------------------------------
>
> Message: 2
> Date: Sun, 17 Apr 2005 05:33:12 EDT
> From: G3rzp@aol.com
> Subject: Re: [Amps] fl2100b part 3
> To: knormoyle@comcast.net, amps@contesting.com
> Message-ID: <ff.11b136c0.2f938758@aol.com>
> Content-Type: text/plain; charset="US-ASCII"
>
>
> In a message dated 16/04/2005 22:45:21 GMT Standard Time,
> knormoyle@comcast.net writes:
>
> Evidently not.. tube pins can go in pretty much any way, into these
> sockets at least.
>
>
>
> They shouldn't! Not with good quality sockets, anyway. But the UX4 base,
> where two pins are fatter than the other two to give polarisation, can be
> a
> problem with some cheaper/nastier sockets.
>
> 73
>
> Peter G3RZP
>
>
> ------------------------------
>
> Message: 3
> Date: Sun, 17 Apr 2005 05:38:22 EDT
> From: G3rzp@aol.com
> Subject: Re: [Amps] article in Nature, modified Aurora via HF
> tspa
> To: r@somis.org, david.kirkby@onetel.net
> Cc: amps@contesting.com, n3ji@yahoo.com
> Message-ID: <83.25b57edd.2f93888e@aol.com>
> Content-Type: text/plain; charset="US-ASCII"
>
>
> In a message dated 16/04/2005 23:11:05 GMT Standard Time, r@somis.org
> writes:
>
> Which is why accurate readings are done with a calibrated step
> attenuator - using the S-meter only as a relative indicator.
>
>
> But what is the resolution of the S meter? Most S meters have S9 at half
> scale. At the nominal 6 dB/S point, that's a 54 dB range, or to read any
> difference to 1dB requires reading the meter to better than 1%. Note this
> nothing to
> do with accuracy - merely resolution. On a big 6 inch scale meter,
> maybe -
> and that's always assuming that there's no hysteris.
>
> However, it's well known that the ionosphere can be non linear. The
> 'Luxembourg Effect'.
>
> 73
>
> Peter G3RZP
>
>
> ------------------------------
>
> Message: 4
> Date: Sun, 17 Apr 2005 08:46:16 -0400
> From: "Mike Sawyer" <w3slk@uplink.net>
> Subject: Re: [Amps] fl2100b part 3
> To: <G3rzp@aol.com>, <knormoyle@comcast.net>, <amps@contesting.com>
> Message-ID: <001f01c5434b$73c621e0$b64856d1@D9PBT931>
> Content-Type: text/plain; charset="iso-8859-1"
>
> Peter said, "Not with good quality sockets....."
>
> You are right Peter,
> However, if the ceramic style sockets are used, there usually is not a
> problem. It is a different story with the phenolic type. The old Heathkit
> Warrior amp was well known for its problems when replacing the 811's.
> Especially if the tubes had been replaced frequently over the life of the
> amp. The phenolic would wear and you could wind up placing the grids at
> the
> filament potential.
> Mike(y)
> W3SLK
>
>
>
> ------------------------------
>
> Message: 5
> Date: Sun, 17 Apr 2005 10:00:15 -0400
> From: "Will Matney" <craxd1@ezwv.com>
> Subject: Re: [Amps] Intermittent Bird element
> To: amps@contesting.com
> Message-ID: <200504171000150190.07ABAF13@mail.ezwv.com>
> Content-Type: text/plain; charset="us-ascii"
>
> Paul,
>
> Ohhh, Is that the way you all fudge those readings?
>
> LOLOL...Just Kiddin
>
> Couldn't resist
>
> Best,
>
> Craxd
>
> *********** REPLY SEPARATOR ***********
>
> On 4/17/05 at 10:00 AM Paul Higginson wrote:
>
>>In message <001901c54317$6f8dcd00$0301a8c0@home>, Steve Thompson
>><g8gsq@ic24.net> writes
>>>Jeff wrote:
>>>> I recently bought a 2500C Bird Element. It worked fine for
>>>> abit but then developed a intermittent problem. I can only
>>>> make it work by tapping on top of the element every time,
>>>> otherwise it drops to zero. Any way to fix this or send for repair??
>>
>>I recently had a similar problem with a 1000D element which exhibited
>>similar symptoms.
>>
>>In this particular one there was a small cal pot which the wiper had
>>gone O/C. Wiggling the pot about cured the problem here - but of course
>>you then need to "calibrate" the unit. - hope that doesn't re start the
>>old thread :-)
>>
>>Access to the pot is obtained in the usual way by gently- carefully-
>>lifting the label cap off by gently - carefully- warming the units face
>>and gently- carefully- easing it off with a sucker and 10a scalpel
>>blade.
>>
>>HTH
>>--
>>73 de Paul GW8IZR
>>(IO73TI Anglesey)
>>_______________________________________________
>>Amps mailing list
>>Amps@contesting.com
>>http://lists.contesting.com/mailman/listinfo/amps
>
>
>
>
>
> ------------------------------
>
> Message: 6
> Date: Sun, 17 Apr 2005 15:10:10 +0100
> From: Paul Higginson <GW8IZR@greenrover.demon.co.uk>
> Subject: Re: [Amps] Intermittent Bird element
> To: craxd1@ezwv.com
> Cc: amps@contesting.com
> Message-ID: <H3$nWUeC5mYCFwwY@greenrover.demon.co.uk>
> Content-Type: text/plain;charset=us-ascii;format=flowed
>
> In message <200504171000150190.07ABAF13@mail.ezwv.com>, Will Matney
> <craxd1@ezwv.com> writes
>>Paul,
>>
>>Ohhh, Is that the way you all fudge those readings?
>>
>>LOLOL...Just Kiddin
>>
>>Couldn't resist
>>
>>Best,
>>
>>Craxd
>>
>
> I could make a batch of special amateur spec units , bit like European
> car speedometers :-)))
>
> Regards Paul
> --
> 73 de Paul GW8IZR
> (IO73TI Anglesey)
>
>
> ------------------------------
>
> Message: 7
> Date: Sun, 17 Apr 2005 08:21:54 -0700
> From: R.Measures <r@somis.org>
> Subject: Re: [Amps] article in Nature, modified Aurora via HF
> tspa
> To: G3rzp@aol.com
> Cc: n3ji@yahoo.com, amps@contesting.com
> Message-ID: <69b408e05458a3261b243e546ae7ca77@somis.org>
> Content-Type: text/plain; charset=US-ASCII; format=flowed
>
> On Apr 17, 2005, at 2:38 AM, G3rzp@aol.com wrote:
>
>> But what is the resolution of the S meter?
>
> With the AGC off, and the RF gain backed down, there's plenty. The
> step-attenuator method is the gold standard.
>
> Richard L. Measures, AG6K, 805.386.3734. www.somis.org
>
>
>
> ------------------------------
>
> Message: 8
> Date: Sun, 17 Apr 2005 08:33:19 -0700 (PDT)
> From: John Irwin <crazytvjohn@yahoo.com>
> Subject: [Amps] grid dip meters
> To: amps@contesting.com
> Message-ID: <20050417153319.76317.qmail@web21001.mail.yahoo.com>
> Content-Type: text/plain; charset=us-ascii
>
> dudes
> I need to get a dip meter.
> I don't know much about what is available or a good one to get, please
> advise me
>
> I search ebay and found many used including kit units and james millen
> units. also a new mfj unit. What do I need in a dip meter, for diping
> plate chokes and pi networks input coils etc.
>
> Thanks for any help
> john kb9tc
>
>
> ---------------------------------
> Do you Yahoo!?
> Plan great trips with Yahoo! Travel: Now over 17,000 guides!
>
> ------------------------------
>
> Message: 9
> Date: Sun, 17 Apr 2005 11:42:28 -0400
> From: "Will Matney" <craxd1@ezwv.com>
> Subject: Re: [Amps] Intermittent Bird element
> To: amps@contesting.com
> Message-ID: <200504171142280230.080947B3@mail.ezwv.com>
> Content-Type: text/plain; charset="us-ascii"
>
> Seriously, I thought about making a line of meters similar to the old
> Drake and actually made a couple of prototypes. To be very honest, those
> can be just as accurate as any Bird I've seen. Bird is about like buying
> the name Cadillac when other cars get you there just as good. That's my
> opinion of course. Actually, a transformer coupled sensor is more wide
> banded than the strip line type like a Bird. Using a toroidal tranny with
> about 40-50 turns C.T. on it and the RF line running through it will go a
> good bit wide banded. The frequency is selected with the toroids material
> like 43, 61 or other. The Bird uses a super short strip line and the
> reason behind that is the amount of power range it has. The lines length
> has to be shorter as the power goes up or the works can become overloaded.
> Or was the way I read about strip line meters. But, for a narrower
> bandspread, a stripline sensor is a good meter. On a Bird, the stripline
> is formed by the back end of the element being paral
> lel with the troughline section enclosed in the "T". By rotating it 180
> deg. gives the fwd. and rev. functions. In other meters, two seperate
> strips are used with the rectifiers connected at opposite ends. These
> strips are placed on either side of the trough line strip. The fwd. and
> rev. is then simply selected by a switch. One good thing about this setup
> is an SWR meter can be made which works at the flick of a switch. There's
> another variance of this where the strip lines are only used for the SWR
> meter and the power is measured by directly measuring the RF voltage off
> the trough line strip. I actually like these types better and was what I
> made in one prototype. I noticed, I think QRO, used a transformer coupled
> type for the internal power meter on their amps. It was mounted at the
> back end near the antenna relay. One thing here, the transformer type
> don't take up as much room as a strip line type. For up to about 2 KW, the
> line length is close to 4 inches long plus the p
> c board length (say 2-1/2 x 5) where the transformer might take up a space
> of 1-1/2 - 2 inches max for the sensor. One in an amp has to be wide
> banded enough to be accurate over the full bandwidth too.
>
> To calibrate, you can accurately measure the RF voltage off the line with
> a scope, calculate the results, then adjust the meters readout
> accordingly. That's about the most accurate way I know without having some
> expensive equipment. That should get you around 3% or more accuracy I
> would think, and is the way mentioned in several books on the subject. To
> be honest, I'm leary of adjusting watt meters by having two meters in line
> and adjusting one from the other. I've seen meters set this way, and after
> taking one out of line, get a different reading with the same amount of
> power applied. I would think it was due to the line lengths where a meter
> and a 3' jumper was taken in and out?
>
> On meters of the same type, let's say we had two meters with +/- 5%
> accuracy. What if one meter was at - 5% and the other was at +5%? The
> difference between each would be an error of 10% which is a good amount.
> That's why I think there's some errors showing between two of the same
> meter. On the manufacturing line, they set each meter to the specs and the
> allowable tolerance they give. A difference of 10% between two would be
> easily done this way I would think if the tech doing it didn't try to set
> them on the money. I wouldn't doubt if this isn't the cause between
> S-meter readings too. 10% dont sound like a lot but on 1 KW it's 100 watts
> on the difference between two. Also, what if you used a meter 5% off, and
> calibrated another. Then, used the newly calibrated one to calibrate
> another and the tech sets it say -5% again. That's a -10% error and can
> grow each time it's done. I have actually seen this done more than once. A
> guy sent off a meter to get calibrated by another shop
> . He gets it back and calibrates someone elses meter with it. When I got
> the meter off that guy, it had I think an error of about 9% if I recall. I
> then sent it back to the manufacturer to have it calibrated and that's
> what they told me it was off by. Then, we cant forget those golden
> screwdrivers out there on used equipment.
>
> We all could rattle on and on about this, but I just wanted to mention
> about accuarcy error and the two types of commonly used watt meters and
> their differences.
>
> Best,
>
> Will
>
> *********** REPLY SEPARATOR ***********
>
> On 4/17/05 at 3:10 PM Paul Higginson wrote:
>
>>In message <200504171000150190.07ABAF13@mail.ezwv.com>, Will Matney
>><craxd1@ezwv.com> writes
>>>Paul,
>>>
>>>Ohhh, Is that the way you all fudge those readings?
>>>
>>>LOLOL...Just Kiddin
>>>
>>>Couldn't resist
>>>
>>>Best,
>>>
>>>Craxd
>>>
>>
>>I could make a batch of special amateur spec units , bit like European
>>car speedometers :-)))
>>
>>Regards Paul
>>--
>>73 de Paul GW8IZR
>>(IO73TI Anglesey)
>
>
>
>
>
> ------------------------------
>
> Message: 10
> Date: Sun, 17 Apr 2005 11:52:25 -0400
> From: "Will Matney" <craxd1@ezwv.com>
> Subject: Re: [Amps] grid dip meters
> To: amps@contesting.com
> Message-ID: <200504171152250430.081264E2@mail.ezwv.com>
> Content-Type: text/plain; charset="us-ascii"
>
> John,
>
> A good one if the Hethkit solid state model. I forget the model number for
> sure but you'll know it when you see it. It will have a green front on it
> and a rectangular meter. I think the model is a 1250 but dont hold me to
> that. It will also be in a gray plastic case with about 6 coils which are
> color coded. The coils have a RCA jack on them for the solid state model.
> The old tube type Heathkits are grey in color, a round meter, have larger
> coils, and come in a cardboard box. The MFJ aint too bad as I have one of
> those also. Actually MFJ dont make them but an Asian company does. The
> same meter was used by Leader Instruments too. The old Millens will be
> getting hard to get parts for so you might want to watch on those. There's
> also only one model of these thats solid state too, the rest being tube.
> There's several other brands but I think the best is a Military model made
> which was a two piece unit. It was tube type though but built like a tank.
> I forget the model number for it
> now. On eBay, you can expect to pay up to $50 - $75 for a good clean
> Heathkit or a MFJ used. The new MFJ is around $125 I think. Hope this
> helps.
>
> Best,
>
> Will
>
> *********** REPLY SEPARATOR ***********
>
> On 4/17/05 at 8:33 AM John Irwin wrote:
>
>>dudes
>>I need to get a dip meter.
>>I don't know much about what is available or a good one to get, please
>>advise me
>>
>>I search ebay and found many used including kit units and james millen
>>units. also a new mfj unit. What do I need in a dip meter, for diping
>>plate chokes and pi networks input coils etc.
>>
>>Thanks for any help
>>john kb9tc
>>
>>
>>---------------------------------
>>Do you Yahoo!?
>> Plan great trips with Yahoo! Travel: Now over 17,000 guides!
>>_______________________________________________
>>Amps mailing list
>>Amps@contesting.com
>>http://lists.contesting.com/mailman/listinfo/amps
>
>
>
>
>
> ------------------------------
>
> _______________________________________________
> Amps mailing list
> Amps@contesting.com
> http://lists.contesting.com/mailman/listinfo/amps
>
>
> End of Amps Digest, Vol 28, Issue 43
> ************************************
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