Message	Date	From	Subject
3801	2009-11-24 09:18:59	c6alk	Ancient FT-243 Xtal Circuits?
Folks: I checked my edition of EMRFD, but I could not find an answer to my question. I just received, for practically no charge, many old WWII crystals. They are marked from about 20 MHz. up to 70 MHz. Most are in the 30 MHz. range. I have a home brew crystal tester that works very well with fundamental mode crystals that I have checked over the years. However, the checker will not oscillate whatsoever with these older crystals. Could these older crystals be overtone types? If so, I know that I need another type of circuit for them to be checked. However, it was my understanding that the overtone technology was developed sometime after WWII. Could the crystal's label indicate the frequency value when multiplied up from the actual oscillation frequency of the crystal? This then would mean that they should oscillate in my tester. I am just curious what circuit that I could breadboard that would allow these ancient beasts to oscillate, and allow me to measure the actual frequency of each. Brian K7RE
3802	2009-11-24 10:54:46	Francis DUPONT	Re: Ancient FT-243 Xtal Circuits?
Hi Brian, > I just received, for practically no charge, many old WWII crystals. > They are marked from about 20 MHz. up to 70 MHz. Most are in the 30 MHz. range. They looks like FT241 Xtal series > Could the crystal's label indicate the frequency value when multiplied up > from the actual oscillation frequency of the crystal? Yes. For the 2 digit series: The actual fundamental frequency is the marked frequency divided by 54. The fundamental frequency is also equal to: (20 + Channel/10) / 54 For the 3 digit series: The actual fundamental frequency is the marked frequency divided by 72 (or the channel number divided by 720). To make short, these are LF crystals in the 300 - 500 kHz range. > I am just curious what circuit that I could breadboard that would allow > these ancient beasts to oscillate, and allow me to measure the actual frequency of each. I have one in my attic, but where!!! I will look tomorrow and give you more infos. 73 Francis F6HSI GQRP #3553
3803	2009-11-24 11:07:35	Tim	Re: Ancient FT-243 Xtal Circuits?

3804	2009-11-25 07:38:27	c6alk	Re: Ancient FT-243 Xtal Circuits?
Hello Francis: Well, thank you very much for that information. I never would have guessed that these crystals would be cut for such low frequency! And here I thought that I was a true old time ham! You saved me a lot of work. If you can find the circuit with not too much trouble. I would appreciate that very much. Meanwhile I will check out low frequency circuits as opposed to the high frequency ones that I was formally searching. Brian K7RE
3805	2009-11-25 07:45:19	c6alk	Re: Ancient FT-243 Xtal Circuits?
Hi Tim: Well, thank you and Francis very much for that information. You both saved me a lot of time in trying to get these crystals to oscillate at high, rather than low frequencies. I even took a few apart, thinking that perhaps I could get a general idea of the fundamental frequency for which they were cut by the shape or thickness of the actual crystal element. That proved unsuccessful. I have been successful in building crystal filters, mostly narrow CW types, but at frequencies that were much higher. It could be fun to lash up a circuit to see how well these crystals do as low frequency IF filters. BTW, I receive this mail group by digest, so my replies take a bit longer to appear. Brian K7RE
3808	2009-11-26 07:22:28	Alan Melia	Re: Ancient FT-243 Xtal Circuits?
Hi Brian the appropriate "channels" were very often usen in half-lattice configuration for 465 and 470 kHz IF filters in the 1950s and 60s. (455 only came along later!) I am sure you will find many articles on this in the journals and Handbooks of the period. Alan G3NYK
3809	2009-11-26 08:03:28	g3oth	Re: Ancient FT-243 Xtal Circuits?
Alan, although I wasn't yet born, I have it on good authority that 455 KHz was being used quite early on as a standard IF both in the USA as well as here in GB, the preferred choice of 465 and 470 was made here later to reduce heterodyne problems being experienced using that IF when tuning 910 KHz which was the QRG of the London BBC TX. Having said that, Hallicrafters and National also used IFs slightly off 455 from time to time and our own Eddystone Company chose 450. To top it all the R1155 used 560 if I am not mistaken, and a BFO QRG of 280 to avoid pulling. Many earlier Single Superhets of course in the 1920s and 1930s for reasons of selectivity, stability and gain used much lower IFs on both sides of the pond, before they came back into vogue in the late 1940s when the Double Superhet was born, and the image problem was solved, but we will not go further into that here. As you say, there are loads of articles using these Surplus Xtals in old Journals, many of which are reproduced
3810	2009-11-26 12:52:36	R Wall	Re: Ancient FT-243 Xtal Circuits?
Hi all, The beauty of the FT243 crystals was that, we were able to change the frequency by using grinding paste that was used to polish gem stones. I have two crystals that I changed the frequency from 5397.5KHz and 4852.5KHz to 8025KHz and 8035KHz. I used these crystals when I had a novice call VK3NKT (Morse code at 5WPM) as we had to be crystal locked and weren't allowed to use a VFO. Even though I also had a limited VHF/UHF VK3YBR call (no Morse code but full theory). The novice call allowed me to operate the HF frequencies. The 4852.5KHz crystal also had stamped on it: "RECEIVER TO RECEIVE ON 4397.5Kc" Note "Kc" (K cycles) not "KHz". This made the IF frequency 455Kc (455KHz). I was allowed to use a VFO on HF when I received the Full call VK3BKO (10WPM). From memory I think you were able to lower the frequency by rubbing solder onto the crystal. Regards, Roderick Wall, vk3yc. P.S. changed to the two letter call when the Wireless Institute of Australia had the two letter call ballot. ----- Original Message -----
3812	2009-11-26 13:19:22	R Wall	Re: Ancient FT-243 Xtal Circuits?
Hi Brian, In case you want to change the frequency of your FT243 crystals: I used a flat piece of glass as a base to grind the crystal on. Think I used water with the finest gem stone grinding paste and moved the crystal in an even figure 8 movement to evenly grind the crystal. Others may want to make a comment on how they did their crystals. Regards, Roderick Wall, vk3yc. ----- Original Message -----
3813	2009-11-26 13:23:56	w4zcb	Re: Ancient FT-243 Xtal Circuits?
used a flat piece of glass as a base to grind the crystal on. Think I used water with the finest gem stone grinding paste and moved the crystal in an even figure 8 movement to evenly grind the crystal. Others may want to make a comment on how they did their crystals. Regards, Roderick Wall, vk3yc. Scouring powder and even toothpaste works too. W4ZCB [Non-text portions of this message have been removed]
3814	2009-11-26 13:25:11	Stephen Wandling	Re: Ancient FT-243 Xtal Circuits?
This brings back memories! I recall using the piece of glass and the figure 8 movements, but I'm sure I didn't have gem grinding paste. Maybe I used Bicarbonate of Soda? Something like that. And to drop the crystal a bit, we would 'scribble' on them with a very soft lead pencil! 72 Stephen VE7NSD R Wall wrote: > Hi Brian, > > In case you want to change the frequency of your FT243 crystals: > > I used a flat piece of glass as a base to grind the crystal on. Think I used water with the finest gem stone grinding paste and moved the crystal in an even figure 8 movement to evenly grind the crystal. Others may want to make a comment on how they did their crystals. > > Regards, > > Roderick Wall, vk3yc. > > ----- Original Message ----- >
3815	2009-11-26 13:29:07	Stephen Wandling	Re: Ancient FT-243 Xtal Circuits?
That's what it was! We used tooth powder instead of paste (poverty) and that's what I used on the crystals. w4zcb wrote: > Scouring powder and even toothpaste works too. > > W4ZCB >
3816	2009-11-26 13:39:52	g3oth	Re: Ancient FT-243 Xtal Circuits?
Hi Rod, Actually this thread should have been entitled FT-24i Xtals, because they are in fact what the originator has, and their outline is somewhat different to the FT-243 ones and have channel numbers etc. for reasons as pointed out earlier. But you are quite right about those FT-243 Xtals which you have there as they were marked for operati
3817	2009-11-26 13:45:22	g3oth	Re: Ancient FT-243 Xtal Circuits?
Still got it wrong didn't I FT-241 not FT-24i Sorry cant see and only a hunt and peck typist. 73 de G3OTH
3818	2009-11-26 13:52:45	R Wall	Re: Ancient FT-243 Xtal Circuits?
The gem stone paste was a black powder that turned into a paste when you added water (think it was water). My father also used it to grind the edges of glass bottles. Roderick Wall, vk3yc. ----- Original Message -----
3819	2009-11-26 14:19:44	R Wall	Re: Ancient FT-243 Xtal Circuits?
Hi Rus, I have the crystals in front of me and I've put them on my N2PK VNA and the frequencies are correct as I've stated. Except the 8025KHz is really Fs 8024.00277KHz and Fp 8026.9066KHz with a Q of 36586.57, according to the N2PK VNA and myVNA. OK on the difference between the FT243 and FT241 crystals, that I didn't know. How long and how much material was removed, this was about 33 years ago and that I don't remember. Regards, Roderick Wall, vk3yc. ----- Original Message -----
3820	2009-11-26 14:41:54	g3oth	Re: Ancient FT-243 Xtal Circuits?
Ok Rod FB abt them being up on 8Mhz after all. I was assuming you had wanted to use & put them on 40 meters. Sounds like nice instrumentation you have there. I last ground my FT-243s using a glass plate and pink Dentist's polishing paste, but only wanted to move them a few KHz. I think the FT-241 men used Hydroflouric Acid to shift those FT-241 types as if you look inside them the Xtal is very thin compared with the FT-243 types. You would think it would be the other way around, so they were probably cut at a different angle in the original quartz. 73 de Russ G3OTH
3821	2009-11-26 15:25:02	R Wall	Re: Ancient FT-243 Xtal Circuits?
Hi Rus, From memory I think I used the 8MHz crystal as an external oscillator that plugged into the old FT200 external VFO plug. To operate in the novice section of the 80 meter band. The N2PK VNA is a great piece of home-brew test equipment, as Harold w4zcb says, a lab in a box. And something that an amateur can build. OK on the FT241 crystals being thinner, I don't have any I only have the FT243 crystals. Regards, Roderick Wall, vk3yc. ----- Original Message -----
3822	2009-11-27 08:42:15	santaj672	Re: Ancient FT-243 Xtal Circuits?
Someone mentioned 'loading' the xtal with pencil lead to move the freq up. When I was a novice, an old timer passed on his tip which worked even better: paint the crystal with mercurochrome. - WA0PWK
3823	2009-11-27 09:39:57	popmedkoh	Re: Ancient FT-243 Xtal Circuits?

3824	2009-11-27 09:46:41	w4zcb	Re: Ancient FT-243 Xtal Circuits?
Someone mentioned 'loading' the xtal with pencil lead to move the freq up. When I was a novice, an old timer passed on his tip which worked even better: paint the crystal with mercurochrome. - WA0PWK That's the wrong direction. You remove material to move the frequency up, you add material to LOWER the frequency. W4ZCB [Non-text portions of this message have been removed]
3825	2009-11-27 09:56:46	g3oth	Re: Ancient FT-243 Xtal Circuits?
Hi Rod I googled the N2PK VNA while you have been sleeping down under in VK and although I couldnt get the direct link to Paul Kiciak, N2PK pages to work for me here, I have been reading up on related info at: http://www.makarov.ca/vna.htm Is this the recommended and approved place to go now for the most recent and up to date info on pcbs, parts, kits etc. etc. or are there other sources I should look at ? I saw some photos from Harold W4ZCB on that site so guess I am roughly in the correct area. Looks like there is a Basic Version and at least two more add ons for VHF and UHF work. Perhaps you, Harold or others could put me in the picture regarding complexity, time and $$$ involved to get your builds up and running (I know thats like asking how long is a piece of string), but nevertheless would be useful, or reply to me off list to save
3827	2009-11-27 10:17:49	w4zcb	Re: Ancient FT-243 Xtal Circuits?
I googled the N2PK VNA while you have been sleeping down under in VK and although I couldnt get the direct link to Paul Kiciak, N2PK pages to work for me here, I have been reading up on related info at: http://www.makarov.ca/vna.htm Is this the recommended and approved place to go now for the most recent and up to date info on pcbs, parts, kits etc. etc. or are there other sources I should look at ? The N2PK website is moderated and you'll have to apply for membership at http://groups.yahoo.com/group/N2PK-VNA/ If you'll do so, I promise to let you in. W4ZCB [Non-text portions of this message have been removed]
3828	2009-11-27 10:20:10	w4zcb	Re: Ancient FT-243 Xtal Circuits?
Also: A detailed desciption of this VNA can be found at: http://n2pk.com W4ZCB [Non-text portions of this message have been removed]
3829	2009-11-27 10:37:06	g3oth	Re: Ancient FT-243 Xtal Circuits?
Tnx agn Harold, Am reading there now. Vy interesting. Russ G3OTH
3830	2009-11-27 10:38:42	g3oth	Re: Ancient FT-243 Xtal Circuits?
Tnx Harold I have just taken up your offer ! 73 de Russ G3OTH
3831	2009-11-27 11:01:59	santaj672	Re: Ancient FT-243 Xtal Circuits?
Yes, I did mean to "lower" the freq. Sorry, hadn't had enough coffee yet this morning to counteract yesterday's Thanksgiving turkey. I had no idea how valuable the bottle of mercurochrome is that's still in my medicine cabinet. At the rate I'm using it, it should outlast me. -WA0PWK
3832	2009-11-27 13:43:15	R Wall	Re: Ancient FT-243 Xtal Circuits?
Hi Rus, I see that you now have the good oil on the N2PK VNA. I remember seeing in a old ARRL SSB handbook on how to use FT243 crystals to build a SSB filter. It wasn't until I had the N2PK VNA that I was able to build a SSB filter, something I always wanted to do. A local supplier here had 50 crystals for $7.50. It was easy using my N2PK VNA and myVNA software. myVNA numbers and logs the parameters for each crystal into a Microsoft Excel or OpenOffice Cal file. Where you can use the data sort tool to sort them into groups for suitable filters. Plugging the parameters into a suitable filter program, and I had a SSB filter all within two hours. Then to use the N2PK VNA and myVNA to measure the SSB filter at 50 ohm. And use myVNA's matching tool to display the band pass of the filter as if it was matched correctly at it's correct impedance. Then to print or copy/paste the results with markers into Microsoft word. BTW, I used Jack Smith's crystal test set. But the magic is, all this for the cost of parts. Now that's Amateur Radio at its best. Thanks, Paul, Dave, Tom, Ivan and everyone else who was involved. Roderick Wall, vk3yc. ----- Original Message -----
3833	2009-11-27 14:17:38	Dave	Re: Ancient FT-243 Xtal Circuits?

3834	2009-11-27 14:32:25	Dave	Re: Ancient FT-243 Xtal Circuits?

3835	2009-11-27 14:35:01	Dave	Re: Ancient FT-243 Xtal Circuits?

3836	2009-11-27 14:40:19	Dave	Re: Ancient FT-243 Xtal Circuits?

3837	2009-11-27 17:00:20	g3oth	Re: Ancient FT-243 Xtal Circuits?

3838	2009-11-27 17:17:17	g3oth	Re: Ancient FT-243 Xtal Circuits?

3839	2009-11-27 17:52:15	w4zcb	Re: Ancient FT-243 Xtal Circuits?
, I have an old pre WW11 6 volt push button Variable Capacitor tuned UX tube example of one of those here, which uses that IF, also have just dug out an old Bliley Model 1C Xtal Controlled Test Oscillator popular in the 1940s that has internal Xtals switched to give 175, 200, 262, 370, 455, 465 1000 KHz Outputs, used for IF and RF Calibration purposes, which would confirm this. Ok re the Hydrofluoric Acid dangers. I have had about 2 pints of the stuff in my garage for the past 20 years so keep it very very safe, as I would have a job to procure it now, and be very bad news if it got into the wrong hands. Never used any of that Mercury based stuff previously mentioned though. 73 de Russ G3OTH What on earth do you store the stuff in? It eats glass. W4ZCB [Non-text portions of this message have been removed]
3841	2009-11-28 02:59:15	g3oth	Re: Ancient FT-243 Xtal Circuits?
--- In emrfd@yahoogroups.com, "w4zcb" wrote > > What on earth do you store the stuff in? It eats glass. > Harold, I keep it in Polyethelene / Teflon Containers. See picture at: http://en.wikipedia.org/wiki/Hydrofluoric_acid You oould buy HF from local chemists here once upon a time for Glass Etching, another interest of mine, see nice article at: http://www.buildingconservation.com/articles/glass98/glass98.htm 73 de Russ G3OTH
3843	2009-11-28 07:52:47	w1kilofoxtrot	Re: Ancient FT-243 Xtal Circuits?
There were a couple of things one could do. Grinding was one, of course, for major frequency shifts. Pencil lead loading too, for dropping the resonance. But I used to tap the cover plate, and insert a 6-32 screw, bearing on the middle of the metal crystal holding plate. I could use that to tune the crystal 'on the fly'. I only wish I could remember how far it used to pull... it was 40 years ago, when I first got my novice ticket... You might want to give that a spin! 73, Steve W1KF
3844	2009-11-28 08:54:30	k5nwa	Re: Ancient FT-243 Xtal Circuits?
At 04:58 AM 11/28/2009, you wrote: > > > > >--- In emrfd@yahoogroups.com, >"w4zcb" wrote > > > > What on earth do you store the stuff in? It eats glass. > > > >Harold, I keep it in Polyethelene / Teflon Containers. See picture at: > ><http://en.wikipedia.org/wiki/Hydrofluoric_acid>http://en.wikipedia.org/wiki/Hydrofluoric_acid > >You oould buy HF from local chemists here once upon a time for Glass >Etching, another interest of mine, see nice article at: > ><http://www.buildingconservation.com/articles/glass98/glass98.htm>http://www.buildingconservation.com/articles/glass98/glass98.htm > >73 de Russ G3OTH I recall reading a long time ago that bees wax would also protect the container containing the acid.. Cecil k5nwa www.softrockradio.org www.qrpradio.com < http://parts.softrockradio.org/ > Never take life seriously. Nobody gets out alive anyway.
3845	2009-11-29 06:49:18	Dave	Re: Ancient FT-243 Xtal Circuits?

3846	2009-11-29 06:57:52	Dave	Re: Ancient FT-243 Xtal Circuits?

Message

Date

From

Subject

3801

2009-11-24 09:18:59

c6alk

Ancient FT-243 Xtal Circuits?

Folks:

I checked my edition of EMRFD, but I could not find an answer to my question. I just received, for practically no charge, many old WWII crystals. They are marked from about 20 MHz. up to 70 MHz. Most are in the 30 MHz. range.

I have a home brew crystal tester that works very well with fundamental mode crystals that I have checked over the years. However, the checker will not oscillate whatsoever with these older crystals.

Could these older crystals be overtone types? If so, I know that I need another type of circuit for them to be checked. However, it was my understanding that the overtone technology was developed sometime after WWII.

Could the crystal's label indicate the frequency value when multiplied up from the actual oscillation frequency of the crystal?

This then would mean that they should oscillate in my tester. I am just curious what circuit that I could breadboard that would allow these ancient beasts to oscillate, and allow me to measure the actual frequency of each.

Brian K7RE

3802

2009-11-24 10:54:46

Francis DUPONT

Re: Ancient FT-243 Xtal Circuits?

Hi Brian,

> I just received, for practically no charge, many old WWII crystals.
> They are marked from about 20 MHz. up to 70 MHz. Most are in the 30

MHz. range.

They looks like FT241 Xtal series

> Could the crystal's label indicate the frequency value when

multiplied up

> from the actual oscillation frequency of the crystal?

Yes.

For the 2 digit series:
The actual fundamental frequency is the marked frequency divided by 54.
The fundamental frequency is also equal to: (20 + Channel/10) / 54

For the 3 digit series:
The actual fundamental frequency is the marked frequency divided by 72
(or the channel number divided by 720).

To make short, these are LF crystals in the 300 - 500 kHz range.

> I am just curious what circuit that I could breadboard that would allow
> these ancient beasts to oscillate, and allow me to measure the actual

frequency of each.

I have one in my attic, but where!!! I will look tomorrow and give you
more infos.

73 Francis

F6HSI GQRP #3553

3803

2009-11-24 11:07:35

Tim

Re: Ancient FT-243 Xtal Circuits?

3804

2009-11-25 07:38:27

c6alk

Re: Ancient FT-243 Xtal Circuits?

Hello Francis:

Well, thank you very much for that information. I never would have guessed that these crystals would be cut for such low frequency! And here I thought that I was a true old time ham! You saved me a lot of work.

If you can find the circuit with not too much trouble. I would appreciate that very much. Meanwhile I will check out low frequency circuits as opposed to the high frequency ones that I was formally searching.

Brian K7RE

3805

2009-11-25 07:45:19

c6alk

Re: Ancient FT-243 Xtal Circuits?

Hi Tim:

Well, thank you and Francis very much for that information. You both saved me a lot of time in trying to get these crystals to oscillate at high, rather than low frequencies. I even took a few apart, thinking that perhaps I could get a general idea of the fundamental frequency for which they were cut by the shape or thickness of the actual crystal element. That proved unsuccessful.

I have been successful in building crystal filters, mostly narrow CW types, but at frequencies that were much higher. It could be fun to lash up a circuit to see how well these crystals do as low frequency IF filters. BTW, I receive this mail group by digest, so my replies take a bit longer to appear.

Brian K7RE

3808

2009-11-26 07:22:28

Alan Melia

Re: Ancient FT-243 Xtal Circuits?

Hi Brian the appropriate "channels" were very often usen in half-lattice
configuration for 465 and 470 kHz IF filters in the 1950s and 60s. (455 only
came along later!) I am sure you will find many articles on this in the
journals and Handbooks of the period.

Alan G3NYK

3809

2009-11-26 08:03:28

g3oth

Re: Ancient FT-243 Xtal Circuits?

Alan, although I wasn't yet born, I have it on good authority that 455 KHz was being used quite early on as a standard IF both in the USA as well as here in GB, the preferred choice of 465 and 470 was made here later to reduce heterodyne problems being experienced using that IF when tuning 910 KHz which was the QRG of the London BBC TX. Having said that, Hallicrafters and National also used IFs slightly off 455 from time to time and our own Eddystone Company chose 450. To top it all the R1155 used 560 if I am not mistaken, and a BFO QRG of 280 to avoid pulling.
Many earlier Single Superhets of course in the 1920s and 1930s for reasons of selectivity, stability and gain used much lower IFs on both sides of the pond, before they came back into vogue in the late 1940s when the Double Superhet was born, and the image problem was solved, but we will not go further into that here.
As you say, there are loads of articles using these Surplus Xtals in old Journals, many of which are reproduced

3810

2009-11-26 12:52:36

R Wall

Re: Ancient FT-243 Xtal Circuits?

Hi all,

The beauty of the FT243 crystals was that, we were able to change the frequency by using grinding paste that was used to polish gem stones. I have two crystals that I changed the frequency from 5397.5KHz and 4852.5KHz to 8025KHz and 8035KHz. I used these crystals when I had a novice call VK3NKT (Morse code at 5WPM) as we had to be crystal locked and weren't allowed to use a VFO. Even though I also had a limited VHF/UHF VK3YBR call (no Morse code but full theory). The novice call allowed me to operate the HF frequencies. The 4852.5KHz crystal also had stamped on it: "RECEIVER TO RECEIVE ON 4397.5Kc" Note "Kc" (K cycles) not "KHz". This made the IF frequency 455Kc (455KHz). I was allowed to use a VFO on HF when I received the Full call VK3BKO (10WPM). From memory I think you were able to lower the frequency by rubbing solder onto the crystal.

Regards,

Roderick Wall, vk3yc.

P.S. changed to the two letter call when the Wireless Institute of Australia had the two letter call ballot.

----- Original Message -----

3812

2009-11-26 13:19:22

R Wall

Re: Ancient FT-243 Xtal Circuits?

Hi Brian,

In case you want to change the frequency of your FT243 crystals:

I used a flat piece of glass as a base to grind the crystal on. Think I used water with the finest gem stone grinding paste and moved the crystal in an even figure 8 movement to evenly grind the crystal. Others may want to make a comment on how they did their crystals.

Regards,

Roderick Wall, vk3yc.

----- Original Message -----

3813

2009-11-26 13:23:56

w4zcb

Re: Ancient FT-243 Xtal Circuits?

used a flat piece of glass as a base to grind the crystal on. Think I used water with the finest gem stone grinding paste and moved the crystal in an even figure 8 movement to evenly grind the crystal. Others may want to make a comment on how they did their crystals.

Regards,

Roderick Wall, vk3yc.

Scouring powder and even toothpaste works too.

W4ZCB

[Non-text portions of this message have been removed]

3814

2009-11-26 13:25:11

Stephen Wandling

Re: Ancient FT-243 Xtal Circuits?

This brings back memories! I recall using the piece of glass and the
figure 8 movements, but I'm sure I didn't have gem grinding paste.
Maybe I used Bicarbonate of Soda? Something like that.

And to drop the crystal a bit, we would 'scribble' on them with a very
soft lead pencil!

72
Stephen
VE7NSD

R Wall wrote:

> Hi Brian,
>
> In case you want to change the frequency of your FT243 crystals:
>
> I used a flat piece of glass as a base to grind the crystal on. Think I used water with the finest gem stone grinding paste and moved the crystal in an even figure 8 movement to evenly grind the crystal. Others may want to make a comment on how they did their crystals.
>
> Regards,
>
> Roderick Wall, vk3yc.
>
> ----- Original Message -----
>

3815

2009-11-26 13:29:07

Stephen Wandling

Re: Ancient FT-243 Xtal Circuits?

That's what it was! We used tooth powder instead of paste (poverty) and
that's what I used on the crystals.

w4zcb wrote:

> Scouring powder and even toothpaste works too.
>
> W4ZCB
>

3816

2009-11-26 13:39:52

g3oth

Re: Ancient FT-243 Xtal Circuits?

Hi Rod,
Actually this thread should have been entitled FT-24i Xtals, because they are in fact what the originator has, and their outline is somewhat different to the FT-243 ones and have channel numbers etc. for reasons as pointed out earlier.
But you are quite right about those FT-243 Xtals which you have there as they were marked for operati

3817

2009-11-26 13:45:22

g3oth

Re: Ancient FT-243 Xtal Circuits?

Still got it wrong didn't I
FT-241 not FT-24i
Sorry cant see and only a hunt and peck typist.
73 de G3OTH

3818

2009-11-26 13:52:45

R Wall

Re: Ancient FT-243 Xtal Circuits?

The gem stone paste was a black powder that turned into a paste when you added water (think it was water). My father also used it to grind the edges of glass bottles.

Roderick Wall, vk3yc.

----- Original Message -----

3819

2009-11-26 14:19:44

R Wall

Re: Ancient FT-243 Xtal Circuits?

Hi Rus,

I have the crystals in front of me and I've put them on my N2PK VNA and the frequencies are correct as I've stated. Except the 8025KHz is really Fs 8024.00277KHz and Fp 8026.9066KHz with a Q of 36586.57, according to the N2PK VNA and myVNA. OK on the difference between the FT243 and FT241 crystals, that I didn't know. How long and how much material was removed, this was about 33 years ago and that I don't remember.

Regards,

Roderick Wall, vk3yc.

----- Original Message -----

3820

2009-11-26 14:41:54

g3oth

Re: Ancient FT-243 Xtal Circuits?

Ok Rod
FB abt them being up on 8Mhz after all.
I was assuming you had wanted to use & put them on 40 meters.
Sounds like nice instrumentation you have there.
I last ground my FT-243s using a glass plate and pink Dentist's polishing paste, but only wanted to move them a few KHz.
I think the FT-241 men used Hydroflouric Acid to shift those FT-241 types as if you look inside them the Xtal is very thin compared with the FT-243 types. You would think it would be the other way around, so they were probably cut at a different angle in the original quartz.
73 de Russ G3OTH

3821

2009-11-26 15:25:02

R Wall

Re: Ancient FT-243 Xtal Circuits?

Hi Rus,

From memory I think I used the 8MHz crystal as an external oscillator that plugged into the old FT200 external VFO plug. To operate in the novice section of the 80 meter band. The N2PK VNA is a great piece of home-brew test equipment, as Harold w4zcb says, a lab in a box. And something that an amateur can build. OK on the FT241 crystals being thinner, I don't have any I only have the FT243 crystals.

Regards,

Roderick Wall, vk3yc.

----- Original Message -----

3822

2009-11-27 08:42:15

santaj672

Re: Ancient FT-243 Xtal Circuits?

Someone mentioned 'loading' the xtal with pencil lead to move the freq up. When I was a novice, an old timer passed on his tip which worked even better: paint the crystal with mercurochrome.
- WA0PWK

3823

2009-11-27 09:39:57

popmedkoh

Re: Ancient FT-243 Xtal Circuits?

3824

2009-11-27 09:46:41

w4zcb

Re: Ancient FT-243 Xtal Circuits?

Someone mentioned 'loading' the xtal with pencil lead to move the freq up. When I was a novice, an old timer passed on his tip which worked even better: paint the crystal with mercurochrome.
- WA0PWK

That's the wrong direction. You remove material to move the frequency up, you add material to LOWER the frequency.

W4ZCB

[Non-text portions of this message have been removed]

3825

2009-11-27 09:56:46

g3oth

Re: Ancient FT-243 Xtal Circuits?

Hi Rod
I googled the N2PK VNA while you have been sleeping down under in VK and although I couldnt get the direct link to Paul Kiciak, N2PK pages to work for me here, I have been reading up on related info at:
http://www.makarov.ca/vna.htm
Is this the recommended and approved place to go now for the most recent and up to date info on pcbs, parts, kits etc. etc. or are there other sources I should look at ?
I saw some photos from Harold W4ZCB on that site so guess I am roughly in the correct area.
Looks like there is a Basic Version and at least two more add ons for VHF and UHF work.
Perhaps you, Harold or others could put me in the picture regarding complexity, time and $$$ involved to get your builds up and running (I know thats like asking how long is a piece of string), but nevertheless would be useful, or reply to me off list to save

3827

2009-11-27 10:17:49

w4zcb

Re: Ancient FT-243 Xtal Circuits?

I googled the N2PK VNA while you have been sleeping down under in VK and although I couldnt get the direct link to Paul Kiciak, N2PK pages to work for me here, I have been reading up on related info at:
http://www.makarov.ca/vna.htm
Is this the recommended and approved place to go now for the most recent and up to date info on pcbs, parts, kits etc. etc. or are there other sources I should look at ?

The N2PK website is moderated and you'll have to apply for membership at

http://groups.yahoo.com/group/N2PK-VNA/

If you'll do so, I promise to let you in.

W4ZCB

[Non-text portions of this message have been removed]

3828

2009-11-27 10:20:10

w4zcb

Re: Ancient FT-243 Xtal Circuits?

Also:
A detailed desciption of this VNA can be found at:

http://n2pk.com

W4ZCB

[Non-text portions of this message have been removed]

3829

2009-11-27 10:37:06

g3oth

Re: Ancient FT-243 Xtal Circuits?

Tnx agn Harold,
Am reading there now.
Vy interesting.
Russ G3OTH

3830

2009-11-27 10:38:42

g3oth

Re: Ancient FT-243 Xtal Circuits?

Tnx Harold
I have just taken up your offer !
73 de Russ G3OTH

3831

2009-11-27 11:01:59

santaj672

Re: Ancient FT-243 Xtal Circuits?

Yes, I did mean to "lower" the freq. Sorry, hadn't had enough coffee yet this morning to counteract yesterday's Thanksgiving turkey.

I had no idea how valuable the bottle of mercurochrome is that's still in my medicine cabinet. At the rate I'm using it, it should outlast me.

-WA0PWK

3832

2009-11-27 13:43:15

R Wall

Re: Ancient FT-243 Xtal Circuits?

Hi Rus,

I see that you now have the good oil on the N2PK VNA. I remember seeing in a old ARRL SSB handbook on how to use FT243 crystals to build a SSB filter. It wasn't until I had the N2PK VNA that I was able to build a SSB filter, something I always wanted to do. A local supplier here had 50 crystals for $7.50. It was easy using my N2PK VNA and myVNA software. myVNA numbers and logs the parameters for each crystal into a Microsoft Excel or OpenOffice Cal file. Where you can use the data sort tool to sort them into groups for suitable filters. Plugging the parameters into a suitable filter program, and I had a SSB filter all within two hours. Then to use the N2PK VNA and myVNA to measure the SSB filter at 50 ohm. And use myVNA's matching tool to display the band pass of the filter as if it was matched correctly at it's correct impedance. Then to print or copy/paste the results with markers into Microsoft word. BTW, I used Jack Smith's crystal test set.

But the magic is, all this for the cost of parts. Now that's Amateur Radio at its best. Thanks, Paul, Dave, Tom, Ivan and everyone else who was involved.

Roderick Wall, vk3yc.

----- Original Message -----

3833

2009-11-27 14:17:38

Dave

Re: Ancient FT-243 Xtal Circuits?

3834

2009-11-27 14:32:25

Dave

Re: Ancient FT-243 Xtal Circuits?

3835

2009-11-27 14:35:01

Dave

Re: Ancient FT-243 Xtal Circuits?

3836

2009-11-27 14:40:19

Dave

Re: Ancient FT-243 Xtal Circuits?

3837

2009-11-27 17:00:20

g3oth

Re: Ancient FT-243 Xtal Circuits?

3838

2009-11-27 17:17:17

g3oth

Re: Ancient FT-243 Xtal Circuits?

3839

2009-11-27 17:52:15

w4zcb

Re: Ancient FT-243 Xtal Circuits?

, I have an old pre WW11 6 volt push button Variable Capacitor tuned UX tube example of one of those here, which uses that IF, also have just dug out an old Bliley Model 1C Xtal Controlled Test Oscillator popular in the 1940s that has internal Xtals switched to give 175, 200, 262, 370, 455, 465 1000 KHz Outputs, used for IF and RF Calibration purposes, which would confirm this. Ok re the Hydrofluoric Acid dangers. I have had about 2 pints of the stuff in my garage for the past 20 years so keep it very very safe, as I would have a job to procure it now, and be very bad news if it got into the wrong hands. Never used any of that Mercury based stuff previously mentioned though.
73 de Russ G3OTH

What on earth do you store the stuff in? It eats glass.

W4ZCB

[Non-text portions of this message have been removed]

3841

2009-11-28 02:59:15

g3oth

Re: Ancient FT-243 Xtal Circuits?

--- In emrfd@yahoogroups.com, "w4zcb" wrote

>
> What on earth do you store the stuff in? It eats glass.
>

Harold, I keep it in Polyethelene / Teflon Containers. See picture at:

http://en.wikipedia.org/wiki/Hydrofluoric_acid

You oould buy HF from local chemists here once upon a time for Glass Etching, another interest of mine, see nice article at:

http://www.buildingconservation.com/articles/glass98/glass98.htm

73 de Russ G3OTH

3843

2009-11-28 07:52:47

w1kilofoxtrot

Re: Ancient FT-243 Xtal Circuits?

There were a couple of things one could do. Grinding was one, of course, for major frequency shifts. Pencil lead loading too, for dropping the resonance. But I used to tap the cover plate, and insert a 6-32 screw, bearing on the middle of the metal crystal holding plate. I could use that to tune the crystal 'on the fly'. I only wish I could remember how far it used to pull... it was 40 years ago, when I first got my novice ticket...

You might want to give that a spin!

73,
Steve
W1KF

3844

2009-11-28 08:54:30

k5nwa

Re: Ancient FT-243 Xtal Circuits?

At 04:58 AM 11/28/2009, you wrote:

>
>
>
>
>--- In emrfd@yahoogroups.com,
>"w4zcb" wrote
> >
> > What on earth do you store the stuff in? It eats glass.
> >
>
>Harold, I keep it in Polyethelene / Teflon Containers. See picture at:
>
><http://en.wikipedia.org/wiki/Hydrofluoric_acid>http://en.wikipedia.org/wiki/Hydrofluoric_acid
>
>You oould buy HF from local chemists here once upon a time for Glass
>Etching, another interest of mine, see nice article at:
>
><http://www.buildingconservation.com/articles/glass98/glass98.htm>http://www.buildingconservation.com/articles/glass98/glass98.htm
>
>73 de Russ G3OTH

I recall reading a long time ago that bees wax would also protect the
container containing the acid..

Cecil
k5nwa
www.softrockradio.org www.qrpradio.com
< http://parts.softrockradio.org/ >

Never take life seriously. Nobody gets out alive anyway.

3845

2009-11-29 06:49:18

Dave

Re: Ancient FT-243 Xtal Circuits?

3846

2009-11-29 06:57:52

Dave

Re: Ancient FT-243 Xtal Circuits?