Re: [time-nuts] Vintage Frequency Measurement

On 2/15/17 3:07 PM, Alberto di Bene wrote: On 2/15/2017 5:29 PM, Tim Shoppa wrote: For those of us who have to translate between the old "cps" and the modern "Hz", I found this handy conversion table on the web: http://www.aqua-calc.com/convert/frequency/hertz-to-cycle-per-second Tim N3QE

Re: [time-nuts] Vintage Frequency Measurement

On 2/15/2017 5:29 PM, Tim Shoppa wrote: For those of us who have to translate between the old "cps" and the modern "Hz", I found this handy conversion table on the web: http://www.aqua-calc.com/convert/frequency/hertz-to-cycle-per-second Tim N3QE Nahhh this is much better :-)

Re: [time-nuts] Vintage Frequency Measurement

Another nice example of "before there were frequency counters": "Methods of using standard-frequency radio transmissions", 1934 http://tf.nist.gov/general/pdf/2423.pdf "Recent developments in precision time-keeping", 1934

Re: [time-nuts] Vintage Frequency Measurement

It may be that they were all once regarded as Wavemeters, i.e. for measuring wavelength, but there was a distinction that is often dropped... the Absorption Wavemeter, as opposed to the "normal" variety. Much like a video recording almost universally referred to as a "video"... a video what?

Re: [time-nuts] Vintage Frequency Measurement

html >> >> iov >> >> >>> Messaggio originale >>> Da: "Tim Shoppa" <tsho...@gmail.com> >>> Data: 15/02/2017 17.29 >>> A: "Discussion of precise time and frequency >>> measurement"<time-nuts@febo

Re: [time-nuts] Vintage Frequency Measurement

com> >> Data: 15/02/2017 17.29 >> A: "Discussion of precise time and frequency measurement"<time-nuts@febo.com> >> Ogg: Re: [time-nuts] Vintage Frequency Measurement >> >> For those of us who have to translate between the old "cps" and the moder

Re: [time-nuts] Vintage Frequency Measurement

017 17.29 >A: "Discussion of precise time and frequency measurement"<time-nuts@febo.com> >Ogg: Re: [time-nuts] Vintage Frequency Measurement > >For those of us who have to translate between the old "cps" and the modern >"Hz", I found this handy co

Re: [time-nuts] Vintage Frequency Measurement

For those of us who have to translate between the old "cps" and the modern "Hz", I found this handy conversion table on the web: http://www.aqua-calc.com/convert/frequency/hertz-to-cycle-per-second Tim N3QE [image: Inline image 1] On Tue, Feb 14, 2017 at 5:29 AM, Peter Vince

Re: [time-nuts] Vintage Frequency Measurement

t; > time-nuts@febo.com> > Sent: Monday, 13 February 2017, 23:46 > Subject: Re: [time-nuts] Vintage Frequency Measurement > > Hi > > With a VFO running, you have a heterodyne frequency meter. That is (at > least to me) > a very different device than an absorption

Re: [time-nuts] Vintage Frequency Measurement

t Atkinson; Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Vintage Frequency Measurement Hi The link gives an error, but I have no doubt that the meaning of the term varies a bit. Thanks for the reference. I’ll try to get it working from here. Bob > On Feb 15, 201

Re: [time-nuts] Vintage Frequency Measurement

cise time and frequency measurement <time-nuts@febo.com> > Sent: Monday, 13 February 2017, 23:46 > Subject: Re: [time-nuts] Vintage Frequency Measurement > > Hi > > With a VFO running, you have a heterodyne frequency meter. That is (at least > to me) > a very diff

Re: [time-nuts] Vintage Frequency Measurement

easurement <time-nuts@febo.com> Sent: Monday, 13 February 2017, 23:46 Subject: Re: [time-nuts] Vintage Frequency Measurement Hi With a VFO running, you have a heterodyne frequency meter. That is (at least to me) a very different device than an absorption wave meter. I know way to pu

Re: [time-nuts] Vintage Frequency Measurement

On 14 February 2017 at 04:23, Raj wrote: > I have a Marconi T.F. 643 C, in Megacycles ! > Ah, a sensible, descriptive name for the unit. Some of these modern units really do Hert(z) :-) Peter ___ time-nuts mailing list --

Re: [time-nuts] Vintage Frequency Measurement

HI What frequency is the crystal and what sized package is it in? Bob > On Feb 14, 2017, at 11:20 AM, Scott Stobbe wrote: > > Taking a second look in the manual, they specifically call out that its not > an AT or BT, so I'm not sure what it would be. > >

Re: [time-nuts] Vintage Frequency Measurement

Hi That was one of the reasons I was a bit amazed high school students were doing it as a lab exercise. The presence of high voltage here and there is something that you simply would not see in a similar school today … Bob > On Feb 13, 2017, at 11:19 PM, Alex Pummer wrote: >

Re: [time-nuts] Vintage Frequency Measurement

just be careful, because if you under-heat the cathode you could kill it 73 Alex On 2/13/2017 7:11 PM, Bob Camp wrote: Hi On Feb 13, 2017, at 8:15 PM, Scott Stobbe wrote: On Mon, Feb 13, 2017 at 6:41 PM, Bob Camp wrote: I think what you would

Re: [time-nuts] Vintage Frequency Measurement

Hi > On Feb 13, 2017, at 8:15 PM, Scott Stobbe wrote: > > On Mon, Feb 13, 2017 at 6:41 PM, Bob Camp wrote: > >> >> >> I think what you would find is that it *is* a fairly normal AT cut and the >> data book >> that came with the instrument plotted

Re: [time-nuts] Vintage Frequency Measurement

On Mon, Feb 13, 2017 at 6:41 PM, Bob Camp wrote: > > > I think what you would find is that it *is* a fairly normal AT cut and the > data book > that came with the instrument plotted out the data for the specific > crystal in > the device. The usable temperature range was fairly

Re: [time-nuts] Vintage Frequency Measurement

-- john, KE5FX Miles Design LLC > -Original Message- > From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Bob > Camp > Sent: Monday, February 13, 2017 3:47 PM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] Vintage F

Re: [time-nuts] Vintage Frequency Measurement

Hi > On Feb 13, 2017, at 10:35 AM, Scott Stobbe wrote: > > Hi Mike, > > First of all, Wow what an interesting read, thanks for sharing some of the > history and your experiences with the 105. A second thanks for uploading > the manual, which I found to be a great

Re: [time-nuts] Vintage Frequency Measurement

Hi With a VFO running, you have a heterodyne frequency meter. That is (at least to me) a very different device than an absorption wave meter. I know way to put power into a BC-221 and use it as an absorption device. I’m not in any way saying that the LM or the 221 are less useful. They are

Re: [time-nuts] Vintage Frequency Measurement

You could use it as an absorption wavemeter, in its broadest sense of a passive tuned circuit with an indicating load. The headphone jack was normally used to calibrate the VFO against a harmonic of the internal crystal oscillator, but it could zero beat an external source as well. It

Re: [time-nuts] Vintage Frequency Measurement

On 2/13/2017 12:56 PM, Brooke Clarke wrote: Wes: Is this the patent for the IMPATT diode power amplifier? https://patents.google.com/patent/US3931587 No. As I recall the designer (or at least a prime mover) was a guy named Eisenhart. The Hughes organization at the time had engineering done

Re: [time-nuts] Vintage Frequency Measurement

On 02/13/2017 10:35 AM, Scott Stobbe wrote: Hi Mike, First of all, Wow what an interesting read, thanks for sharing some of the history and your experiences with the 105. A second thanks for uploading the manual, which I found to be a great read, as with most old test & measurement product

Re: [time-nuts] Vintage Frequency Measurement

The BC-221 was the backbone of WW2 communications. How else were all those sloppy BC-348's and AR-13's set to the called-for frequencies? Same for shipboard. Don On 2017-02-13 13:05, Brooke Clarke wrote: Hi Bob: The BC-221 is usually referred to as either a Frequency Meter or a Heterodyne

Re: [time-nuts] Vintage Frequency Measurement

Hi Bob: The BC-221 is usually referred to as either a Frequency Meter or a Heterodyne Frequency Meter. -- Have Fun, Brooke Clarke http://www.PRC68.com http://www.end2partygovernment.com/2012Issues.html Original Message Hi Ok, so how does that make a BC-221 a wave meter?

Re: [time-nuts] Vintage Frequency Measurement

m> Sent: Sunday, February 12, 2017 11:11 PM Subject: Re: [time-nuts] Vintage Frequency Measurement To put BC-221 things in perspective, the 1 Mc/s reference crystal was adjusted, according to the manual, to within 5 c/s... Things have come a ways since! Dan __

Re: [time-nuts] Vintage Frequency Measurement

On Sun, Feb 12, 2017 at 8:39 AM, Dan Rae wrote: > On 2/11/2017 10:08 PM, Scott Stobbe wrote: > >> I was inspired recently coming across a Lampkin 105 frequency meter, as to >> how frequency measurement was done before counters. >> >> Certainly zero-beating a dial calibrated

Re: [time-nuts] Vintage Frequency Measurement

This reminds me. Many years ago the Titan Missile sites around here in Tucson were being decommissioned. The people at Davis Monthan AFB who maintained them were going to be out of work but had an opportunity to bump into something else on base if they got some more training. I and a

Re: [time-nuts] Vintage Frequency Measurement

The BC-221 was mentioned in a Time-Nuts thread from December, 2015. Copying from my post in that old thread: Back in the early 1970's I took my BC-221 and added a TTL divide by 1,000 (or 2,000 or 4,000 or 8,000) external circuit to generate very precise audio test tones from the RF oscillator.

Re: [time-nuts] Vintage Frequency Measurement

Hi Ok, so how does that make a BC-221 a wave meter? Bob > On Feb 12, 2017, at 7:15 PM, Wes wrote: > > On 2/12/2017 12:51 PM, Bob Camp wrote: >> Hi >> >> Maybe I’ve been wrong for the last many decades … >> >> To me a wave meter is a tuned circuit device that tells you the

Re: [time-nuts] Vintage Frequency Measurement

on an unusual frequency (not a normal route) for which they did >> not have a crystal available. >> >> Alan >> G3NYK >> - Original Message - From: "Dan Rae" <dan...@verizon.net> >> To: "Discussion of precise time and frequency meas

Re: [time-nuts] Vintage Frequency Measurement

Hi If you look at a typical BC-221 in use, it goes from “calibrated” in a nice warm hut to the back of a jeep. It heads out to an ice cold flight line and the switch turns the batteries back on again. It bumps in and out of a batch of B-17’s setting each one up for the day’s net frequencies.

Re: [time-nuts] Vintage Frequency Measurement

On 12 February 2017 at 06:08, Scott Stobbe wrote: > I was inspired recently coming across a Lampkin 105 frequency meter, as to > how frequency measurement was done before counters. > > Certainly zero-beating a dial calibrated oscillator, would be one approach. > > Is

Re: [time-nuts] Vintage Frequency Measurement

- From: "Dan Rae" <dan...@verizon.net> > To: "Discussion of precise time and frequency measurement" < > time-nuts@febo.com> > Sent: Sunday, February 12, 2017 11:11 PM > Subject: Re: [time-nuts] Vintage Frequency Measurement > > > To put BC-221 t

Re: [time-nuts] Vintage Frequency Measurement

cher lines or cavity wavemeters. Robert G8RPI. From: Scott Stobbe <scott.j.sto...@gmail.com> To: Discussion of precise time and frequency measurement <time-nuts@febo.com> Sent: Sunday, 12 February 2017, 6:08 Subject: [time-nuts] Vintage Frequency Measurement I was inspired

Re: [time-nuts] Vintage Frequency Measurement

> More recently, Alan Melia, G3NYK, reports an accuracy of 0.1 Hertz using > the same technique, http://www.alan.melia.btinternet.co.uk/freqmeas.htm . John -- Alan's web site moved from btinternet to http://g3nyk.ham-radio-op.net/ so the new URL is: "Frequency and Time Measurement"

Re: [time-nuts] Vintage Frequency Measurement

Well 5 cycles per second is more than accurate enough.  That translates to a 150 Hz error at 30 MHz, definitely negligible for the uses of all these gear.  There was no official Time Nuts group at the time, although many of us had the spirit.  Yet the capability of the BC-221 far exceeded its

Re: [time-nuts] Vintage Frequency Measurement

for which they did not have a crystal available. Alan G3NYK - Original Message - From: "Dan Rae" <dan...@verizon.net> To: "Discussion of precise time and frequency measurement" <time-nuts@febo.com> Sent: Sunday, February 12, 2017 11:11 PM Subject: Re:

Re: [time-nuts] Vintage Frequency Measurement

Hi That’s not the *accuracy* of the crystal mind you. That’s how close you do the zero beat to something else that is more accurate. The crystal is out in the open and it drifts quite a bit as the unit warms up or changes temperature due to being moved around. Bob > On Feb 12, 2017, at

Re: [time-nuts] Vintage Frequency Measurement

To put BC-221 things in perspective, the 1 Mc/s reference crystal was adjusted, according to the manual, to within 5 c/s... Things have come a ways since! Dan ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to

Re: [time-nuts] Vintage Frequency Measurement

On Sun, 12 Feb 2017 17:16:18 + (UTC), you wrote: >In a word,Wavemeters. Classic US onwas the BC221 with built in 100kHz crystal >calibrator A couple of years ago, I got a BC221 from an estate; had to recap the homebrew power supply the late ham had built for it, but the BC221 worked fine

Re: [time-nuts] Vintage Frequency Measurement

ts@febo.com>; Bob Albert <bob91...@yahoo.com> Sent: Sunday, February 12, 2017 2:49 PM Subject: Re: [time-nuts] Vintage Frequency Measurement   A more accurate way to adjust for zero beat is to tone modulate one of the signals. The waxing and waning of the tone is easier to disc

Re: [time-nuts] Vintage Frequency Measurement

ra...@cox.net> To: Discussion of precise time and frequency measurement <time-nuts@febo.com>; Bob Albert <bob91...@yahoo.com> Sent: Sunday, February 12, 2017 2:49 PM Subject: Re: [time-nuts] Vintage Frequency Measurement A more accurate way to adjust for zero beat is to tone modulate one

Re: [time-nuts] Vintage Frequency Measurement

t; > > - Original Message - > From: "Bob Albert via time-nuts" <time-nuts@febo.com> > To: "Discussion of precise time and frequency measurement" > <time-nuts@febo.com> > Sent: Sunday, February 12, 2017 5:00 PM > Subject: Re: [time-nuts] Vi

Re: [time-nuts] Vintage Frequency Measurement

y 12, 2017 5:00 PM Subject: Re: [time-nuts] Vintage Frequency Measurement First you need a standard, a crystal oscillator. If you want serious precision, you'd have one in an oven. Zero beat that with WWV. Then make a very stable VFO and calibrate the harmonics against the crystal. Assume linear c

Re: [time-nuts] Vintage Frequency Measurement

A more accurate way to adjust for zero beat is to tone modulate one of the signals. The waxing and waning of the tone is easier to discern than for the background noise. "Accurate Zero Beating, another perspective. When trimming an oscillator so it or one of its harmonics zero beats with WWV

Re: [time-nuts] Vintage Frequency Measurement

, NZ > -Original Message- > From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Mike > Garvey > Sent: Monday, 13 February 2017 2:36 a.m. > To: 'Discussion of precise time and frequency measurement' > Subject: Re: [time-nuts] Vintage Frequency Measurement &g

Re: [time-nuts] Vintage Frequency Measurement

So far all the answers are about high-end expensive equipment. There were also low cost frequency meters. I have one 40 years ago that was not expensive. It wa a simple "frequency to voltage" circuit that drove an analog meter. It was made just before the digital multimeters came out, maybe

Re: [time-nuts] Vintage Frequency Measurement

@febo.com> > Sent: Sunday, 12 February 2017, 6:08 > Subject: [time-nuts] Vintage Frequency Measurement > > I was inspired recently coming across a Lampkin 105 frequency meter, as to > how frequency measurement was done before counters. > > Certainly zero-beatin

Re: [time-nuts] Vintage Frequency Measurement

[Hopefully this time my post is in the required plain-text format!] The solid-state HP-5210A and its vacuum-tube predecessors, the HP-500A/B/C family, were analog frequency measuring instruments. The circuitry summed the input frequency (converted into pulses) and generated an analog voltage

Re: [time-nuts] Vintage Frequency Measurement

First you need a standard, a crystal oscillator.  If you want serious precision, you'd have one in an oven.  Zero beat that with WWV.  Then make a very stable VFO and calibrate the harmonics against the crystal.  Assume linear calibration on the VFO between check points. The military LM and

Re: [time-nuts] Vintage Frequency Measurement

From: Scott Stobbe <scott.j.sto...@gmail.com> To: Discussion of precise time and frequency measurement <time-nuts@febo.com> Sent: Sunday, 12 February 2017, 6:08 Subject: [time-nuts] Vintage Frequency Measurement I was inspired recently coming across a Lampkin 105 freq

Re: [time-nuts] Vintage Frequency Measurement

There was also one generator which you could tune to beat the frequency in question the generator was a frequency synthesizer without any digital part that was the famous Schomandl FD! see here SCHOMANDL-FD1-FDM1 FREQUENCY METER,

Re: [time-nuts] Vintage Frequency Measurement

and frequency measurement Subject: Re: [time-nuts] Vintage Frequency Measurement Back in the early sixties I worked in a lab adjusting filters for line transmission. We had numerous oscillators, built to be boat anchors, and CROs set up for X-Y display. The lab had 100hz, 1kHz, 10kHz standards

Re: [time-nuts] Vintage Frequency Measurement

Hi Counters go back at least into the early 1950’s. I started out with fully vacuum tube (except for diodes) counters obtained as surplus in the mid 1960’s. They used some odd gas filled triodes. Everything in them could have been on the market in 1947. They were not a common thing until the

Re: [time-nuts] Vintage Frequency Measurement

On 2/11/2017 10:08 PM, Scott Stobbe wrote: I was inspired recently coming across a Lampkin 105 frequency meter, as to how frequency measurement was done before counters. Certainly zero-beating a dial calibrated oscillator, would be one approach. Google BC-221 and you may get some idea of how

Re: [time-nuts] Vintage Frequency Measurement

Back in the early sixties I worked in a lab adjusting filters for line transmission. We had numerous oscillators, built to be boat anchors, and CROs set up for X-Y display. The lab had 100hz, 1kHz, 10kHz standards wired in. We were expert at recognising lisajou figures. We might have several

Re: [time-nuts] Vintage Frequency Measurement

Hi, With low-pass filters, I think. This is the simplest method: an rc filter and measure is done on the capacitor poles. Ilia. On 02/12/17 06:08, Scott Stobbe wrote: I was inspired recently coming across a Lampkin 105 frequency meter, as to how frequency measurement was done before

[time-nuts] Vintage Frequency Measurement

I was inspired recently coming across a Lampkin 105 frequency meter, as to how frequency measurement was done before counters. Certainly zero-beating a dial calibrated oscillator, would be one approach. Is there a standout methodology or instrument predating counters?