Date   

HP141

Chris Ruddy MM0KOS
 

Hi guys

Im looking for some help regarding the HP141 spectrum analyser and thought the best place to look for some help is here.

There is a cable (08443-60009) required to inter-connect the 8443A to the 8553B via the 141T for the 0 to 110MHZ.

Im wondering if anyone has one of these cables and can check the connections for me before i link up my homebrew effort.

Im looking to see if the cable is connected 1 to 1, 2 to 2 etc as i cannot find any information of it online.

A greatly appreciated Chris if you could take the effort to do this for me.

Thanks Chris MM0KOS


Whitebox Oscillator Diode Replacement.

Mark - M1MPW
 

I recently bought a whitebox system which arrived in a very poor state.
The oscillator 1st stage had several burnt out resistors and the 2nd stage transformer was shorted.
All these easily fixed.
But the diode CR3 on the output of the transformer has a crack in it which has rendered it useless.

Does anyone know of a suitable replacement for the diode?
None of the schematics I can find give part numbers.

Thanks,

Mark


Re: Help with Tektronixs 492 S.A. PSU fault.

geoffrey pike
 

Hi Nick,
Aren't Tantalum caps great!, they always fail. There is nothing worse than a board with no tants on it. I assume the 492 is awkward to work at there was a mention of extender boards previously!. The HP analysers of the 80s have fold out boards,
but some of the older ones in HP182 mainframes are not easy to work with. Hope it keeps going for you
cheers
Geoff
GI0GDP

On Saturday, 16 January 2021, 11:07:11 GMT, Nick Gregory G0HIK via groups.io <nickg0hik@...> wrote:


I didn't know there was group. I'll join that when it fails next time. The heart always misses a beat when you switch on 1980's test kit.

Nick G0HIK


Re: Crystal holder type

Michael Scott
 

Thanks John and Francois, just what I needed!

73, Mike.

On 16/01/2021 13:24, John E. Beech wrote:
Try: http://www.quartslab.com/ click on "holder types"

de John G8SEQ

-------Original Message-------
From: Michael Scott via groups.io <g3lyp=btinternet.com@groups.io>
To: UKMicrowaves@groups.io <UKMicrowaves@groups.io>
Subject: [UKMicrowaves] Crystal holder type
Sent: Jan 16 '21 13:13
Hi All
Does anyone know the correct designation for a crystal holder which
looks like HC49U but is smaller, the dimensions being 8mmx7mmx2mm HxWxD.
The Chipbank has a lot this size and although I have Googled various
descriptions, I haven't found a specification. Presumably somwhere there
is a table of crystal case sizes and specifications as there is for
capacitors etc., but I can't find it. Crystal cases brings up DVD cases
and jewellery items but nothing electronic!
73, Mike, G3LYP.


Re: Baofeng UV-5R output on 10GHz

Clive Elliott GW4MBS
 

After weeks & weeks of hearing nothing, many thanks to Adrian G4UVZ in Taunton for getting a signal across to me. Not very strong but confirms that my rig still works & is till on the correct frequency. It also verified the heading from the field trials with the Baofeng on the prescribed post was spot on for Adrian.

The plan is in addition to changing from 3W to 12W at home with the 1m dish.But to operate "portable" from the top of my upper field from the Land Rover. Previously I had a PU-8 that was relatively weak & was difficult to optimise unless on flat ground. I now have a 5m Hilomast with keyed sections that is considerably more robust which will permanently secured to the Land Rover, this will carry a 65cm dish with elevation control. With height of 5m I will be able to see over our hedge, the lane & the hedge on the other side. Pulling into a carpark on terra firma & putting up a tripod isn't going to cut it round here.

With the present viral situation I suspect my field will be the only portable option for a while to come.
--
Clive GW4MBS (ex-G8ADP)
Pottering on 6m - 3cm in a valley in IO71XW where any QSO is a triumph of optimism over geography!


Re: Baofeng UV-5R output on 10GHz

Clive Elliott GW4MBS
 

Thank you all for replies.

Before discovering the Baofeng phenomenon, I built up a 48MHz module into something from the chipbank. There were two problems.

Firstly it was giving output below 10368.00, so it was not convenient to use with my 2m IF. Secondly it drifted badly. It might have been better if I put it in an insulated box & allowed to warm up period, but this would have been a fiddle for the way I want use a signal source. It is not just a test source for receiver sensitivity & frequency check but for dish alignment, which is especially not obvious as I am in a valley firing up hill.

The Baofeng is very convenient to use & gives a relatively stable signal, I put it in a plastic bag & walk 150m cautiously up to our top field, although this not the top of the hill but the ground rises more gradually thereafter. It is fitted on a designated fence post, I use a 1m dish & have to get it aligned within a degree. When I have worked G4UVZ (Taunton)  I have obviously recorded the heading, subsequently I have placed the Baefong on a post that is in the line of the path.

Periodically I traipse up the field to fit the Baofeng, on return I can get a good S2 signal, which is most reassuring that all is well. I recently reviewed that the dish had been blown 12 degrees off alignment. So I am very happy with the Baofeng but can't understand why the frequency change occurred.

The nearest I have to a Welsh beacon is GW4NOS who can give me a signal which has an ERP of 5W from the Port Talbot area, but again this is only when there is good rain in the right place. I'm not always sure that rain will always represent the true heading.

The traipse up the hill is tiresome because I have to go there a second time to collect the Baefong after the test. It is muddy & mindful that a few yards from the designated post the previous owner collapsed & died have ascended the hill too quickly. 

I'm considering putting the Baofeng in a waterproof box with a solar panel & leaving it up there. Then with a "beacon" I could have daily reassurance that everything is working & ready to go when the opportunities arise, as long periods of nothing heard can undermine confidence in the system!
--
Clive GW4MBS (ex-G8ADP)
Pottering on 6m - 3cm in a valley in IO71XW where any QSO is a triumph of optimism over geography!


Re: Crystal holder type

John E. Beech
 

Try: http://www.quartslab.com/ click on "holder types"

de John G8SEQ

-------Original Message-------
From: Michael Scott via groups.io <g3lyp=btinternet.com@groups.io>
To: UKMicrowaves@groups.io <UKMicrowaves@groups.io>
Subject: [UKMicrowaves] Crystal holder type
Sent: Jan 16 '21 13:13

Hi All

Does anyone know the correct designation for a crystal holder which
looks like HC49U but is smaller, the dimensions being 8mmx7mmx2mm HxWxD.
The Chipbank has a lot this size and although I have Googled various
descriptions, I haven't found a specification. Presumably somwhere there
is a table of crystal case sizes and specifications as there is for
capacitors etc., but I can't find it. Crystal cases brings up DVD cases
and jewellery items but nothing electronic!

73, Mike, G3LYP.







Crystal holder type

Michael Scott
 

Hi All

Does anyone know the correct designation for a crystal holder which looks like HC49U but is smaller, the dimensions being 8mmx7mmx2mm HxWxD. The Chipbank has a lot this size and although I have Googled various descriptions, I haven't found a specification. Presumably somwhere there is a table of crystal case sizes and specifications as there is for capacitors etc., but I can't find it. Crystal cases brings up DVD cases and jewellery items but nothing electronic!

73, Mike, G3LYP.


Re: Baofeng UV-5R output on 10GHz

Andy G4JNT
 

If you want a weak test source at 10Ghz, why not buy yourself a cheap crystal oscillator at 48MHz and connect it to a Schottky diode as a multiplier.   Calibrate the frequency against a beacon.    Bog standard oscillators run at a few quid each.
Picking a couple at random 15 and 20ppm  accuracy

Or go for a 2PPM 38.4MHz (* 270 = 10368MHz) costing a whopping 87p

Mind you, 2PPM is still 20kHz uncertainty on 10GHz.



Virus-free. www.avg.com


On Sat, 16 Jan 2021 at 12:45, Andy Talbot <andy.g4jnt@...> wrote:
You had me intrigued so went and tried mine - tuned to 432.0125

There's a disgusting sounding strong poor quality note at 10368.091 MHz to be found when I place the unsquelched Baofeng near the radio.   The actual RF out of the radio measured as 432.0125137 MHz, which is remarkably good  sub-1ppm accuracy.



Virus-free. www.avg.com

On Sat, 16 Jan 2021 at 12:18, Clive Elliott GW4MBS via groups.io <humber1ton=btinternet.com@groups.io> wrote:
I know some of us use the Baofeng UV-5R 2m/70cm hand-held as a signal marker on 10GHz due to the 24th harmonic of the RX LO highlighted in this article:

https://destevez.net/2016/07/phase-noise-of-a-baofeng-uv-5r-10ghz-signal/

When tuned to 432.0125 it gave me a remarkably stable signal on 10368.22 with a GPS locked Kuhne. When I have been able to go portable the rig calibration was verified by two beacons.

Back home in the valley I am stuck as we have no beacons in Wales so I am reliant on the Baofeng for reassurance that things still work & are on frequency. During heavy rain I can usually hear GB3KBQ & sometimes GB3SCX, unfortunately we have had no useful rain for many weeks nor have I caught a whisper of the two beacons by AS.

Somehow I messed up the settings on the Baofeng so in desperation I did a reset. But immediately after doing that I find the 432.0125 RX output has moved down to 10368.145. I have reset this several times but get the same result.

So my question is, what frequency output on 10GHz do others get when using the Baofeng in this way? Is it giving the "correct" frequency in it's present state or was my earlier set up correct & I have reset it up wrongly?
--
Clive GW4MBS (ex-G8ADP)
Pottering on 6m - 3cm in a valley in IO71XW where any QSO is a triumph of optimism over geography!


Re: Baofeng UV-5R output on 10GHz

Andy G4JNT
 

You had me intrigued so went and tried mine - tuned to 432.0125

There's a disgusting sounding strong poor quality note at 10368.091 MHz to be found when I place the unsquelched Baofeng near the radio.   The actual RF out of the radio measured as 432.0125137 MHz, which is remarkably good  sub-1ppm accuracy.



Virus-free. www.avg.com


On Sat, 16 Jan 2021 at 12:18, Clive Elliott GW4MBS via groups.io <humber1ton=btinternet.com@groups.io> wrote:
I know some of us use the Baofeng UV-5R 2m/70cm hand-held as a signal marker on 10GHz due to the 24th harmonic of the RX LO highlighted in this article:

https://destevez.net/2016/07/phase-noise-of-a-baofeng-uv-5r-10ghz-signal/

When tuned to 432.0125 it gave me a remarkably stable signal on 10368.22 with a GPS locked Kuhne. When I have been able to go portable the rig calibration was verified by two beacons.

Back home in the valley I am stuck as we have no beacons in Wales so I am reliant on the Baofeng for reassurance that things still work & are on frequency. During heavy rain I can usually hear GB3KBQ & sometimes GB3SCX, unfortunately we have had no useful rain for many weeks nor have I caught a whisper of the two beacons by AS.

Somehow I messed up the settings on the Baofeng so in desperation I did a reset. But immediately after doing that I find the 432.0125 RX output has moved down to 10368.145. I have reset this several times but get the same result.

So my question is, what frequency output on 10GHz do others get when using the Baofeng in this way? Is it giving the "correct" frequency in it's present state or was my earlier set up correct & I have reset it up wrongly?
--
Clive GW4MBS (ex-G8ADP)
Pottering on 6m - 3cm in a valley in IO71XW where any QSO is a triumph of optimism over geography!


Re: Baofeng UV-5R output on 10GHz

John Fell
 

Hi Clive ,
Never tried that on a BF but seems a reasonable thing to do/P - would imagine some detectable microphony at 10GHz from the synth ref Xtal and temp drift ?

If you cannot hear KBQ or SCX and bands are extremely flat , like now , you could perhaps Tee of your RX down the chain after downconversion and use a scanner to listen to QO100 .Always activity or the two beacons to hear and loud on a 60cm offset .

HNY
John
G0API

PS Any update on the 10GHz  GW beacon ?

On Sat, 16 Jan 2021 at 12:18, Clive Elliott GW4MBS via groups.io <humber1ton=btinternet.com@groups.io> wrote:
I know some of us use the Baofeng UV-5R 2m/70cm hand-held as a signal marker on 10GHz due to the 24th harmonic of the RX LO highlighted in this article:

https://destevez.net/2016/07/phase-noise-of-a-baofeng-uv-5r-10ghz-signal/

When tuned to 432.0125 it gave me a remarkably stable signal on 10368.22 with a GPS locked Kuhne. When I have been able to go portable the rig calibration was verified by two beacons.

Back home in the valley I am stuck as we have no beacons in Wales so I am reliant on the Baofeng for reassurance that things still work & are on frequency. During heavy rain I can usually hear GB3KBQ & sometimes GB3SCX, unfortunately we have had no useful rain for many weeks nor have I caught a whisper of the two beacons by AS.

Somehow I messed up the settings on the Baofeng so in desperation I did a reset. But immediately after doing that I find the 432.0125 RX output has moved down to 10368.145. I have reset this several times but get the same result.

So my question is, what frequency output on 10GHz do others get when using the Baofeng in this way? Is it giving the "correct" frequency in it's present state or was my earlier set up correct & I have reset it up wrongly?
--
Clive GW4MBS (ex-G8ADP)
Pottering on 6m - 3cm in a valley in IO71XW where any QSO is a triumph of optimism over geography!


Baofeng UV-5R output on 10GHz

Clive Elliott GW4MBS
 

I know some of us use the Baofeng UV-5R 2m/70cm hand-held as a signal marker on 10GHz due to the 24th harmonic of the RX LO highlighted in this article:

https://destevez.net/2016/07/phase-noise-of-a-baofeng-uv-5r-10ghz-signal/

When tuned to 432.0125 it gave me a remarkably stable signal on 10368.22 with a GPS locked Kuhne. When I have been able to go portable the rig calibration was verified by two beacons.

Back home in the valley I am stuck as we have no beacons in Wales so I am reliant on the Baofeng for reassurance that things still work & are on frequency. During heavy rain I can usually hear GB3KBQ & sometimes GB3SCX, unfortunately we have had no useful rain for many weeks nor have I caught a whisper of the two beacons by AS.

Somehow I messed up the settings on the Baofeng so in desperation I did a reset. But immediately after doing that I find the 432.0125 RX output has moved down to 10368.145. I have reset this several times but get the same result.

So my question is, what frequency output on 10GHz do others get when using the Baofeng in this way? Is it giving the "correct" frequency in it's present state or was my earlier set up correct & I have reset it up wrongly?
--
Clive GW4MBS (ex-G8ADP)
Pottering on 6m - 3cm in a valley in IO71XW where any QSO is a triumph of optimism over geography!


Re: Help with Tektronixs 492 S.A. PSU fault.

Nick Gregory G0HIK
 

I didn't know there was group. I'll join that when it fails next time. The heart always misses a beat when you switch on 1980's test kit.

Nick G0HIK


Re: Help with Tektronixs 492 S.A. PSU fault.

Nick Gregory G0HIK
 

Thanks all for the helpful comments.

I've just got it licked, well it looks like it anyway.
It was an overload on the +/- 15v rails. I thought I had disconnected every consumer of the  +/-15v from the motherboard, but hidden under the YIG filter was a supply to the 100MHz L.O. Low and behold there were two +/- 12v regulators, decoupled by Tants. One was S/C but both changed out of course.

Several lessons learnt, every day is a school day, I just need to try and retain it all.

Nick G0HIK


Re: Help with Tektronixs 492 S.A. PSU fault.

geoff wiggins
 

I had a similar type of fault on my Tek 466 storage scope. The supply rail was down to 4.7v approx and that was the clue.

I found a huge current drain and the fault was a short cct 2.2uF capacitor fed from a 4.7v zener which was supposed to feed 10v or so to the trigger pots. Believe it or not this little 400mW zener was taking all that current and didn't blow. The capacitor in question was a small yellow type about the size of the zener. Just follow the track around looking for a short to deck.

Good hunting.

73 Geoff. G4XMJ

On 15/01/2021 18:55, Nick Gregory G0HIK via groups.io wrote:
I came to switching on one time and it light up, but nothing on the display.

The +15 v rail is 4.7v
The -15 v rail is -3.1v.

I think the minus rail uses the plus rail as a reference so it may well be just the + 15v rail faulty.

I've disconnected all cards and connectors and the volts are still low, so I dont think is a card fault and it's probably a PSU fault. The 0.3 ohm resistor in the +15v line says its has a draw of 1.0 amps with seems a lot at 4 volts though.

the +/- 17v rails that feed the +/- 15v are fine.

I would have suspected s/c Tants, but there does not seem to be any tants.

Any help welcomed please.

I've included a part of the circuit with some voltages on.

Thanks Nick G0HIK


Re: Help with Tektronixs 492 S.A. PSU fault.

Mark - M1MPW
 

Is that not a tant by the multiturn preset?
Also... a burnt resistor above the edge connector?

Mark


Re: Request for a broken doner attenuator HP8563 33321

Robin Szemeti - G1YFG
 

You can also ask in this group:


Very helpful people.


On Fri, 15 Jan 2021 at 21:50, Maarten PA0MHE <maarten.heuvelman@...> wrote:
By a stupidity I blew up the control board in the 33321 attenuator in my HP8593 SA, so the attenuation itself is ok but the control logic inside the attenuator is broken.
Normally the RF part of such an attenuator is damaged of such an attenuator by applying too much RF at the input of a SA.
I hope someone has a broken attenuator (RF part) in his junkbox with a still intact control PCB which can be a donor for my attenuator ??????


--
Robin Szemeti - G1YFG


Request for a broken doner attenuator HP8563 33321

Maarten PA0MHE
 

By a stupidity I blew up the control board in the 33321 attenuator in my HP8593 SA, so the attenuation itself is ok but the control logic inside the attenuator is broken.
Normally the RF part of such an attenuator is damaged of such an attenuator by applying too much RF at the input of a SA.
I hope someone has a broken attenuator (RF part) in his junkbox with a still intact control PCB which can be a donor for my attenuator ??????


Re: Help with Tektronixs 492 S.A. PSU fault.

geoffrey pike
 

Hi Nick.
Have you posted this on the Textronics group.io?
Good luck
Geoff
GI0GDP

On Friday, 15 January 2021, 18:55:32 GMT, Nick Gregory G0HIK via groups.io <nickg0hik@...> wrote:


I came to switching on one time and it light up, but nothing on the display.

The +15 v rail is 4.7v
The -15 v rail is -3.1v.

I think the minus rail uses the plus rail as a reference so it may well be just the + 15v rail faulty.

I've disconnected all cards and connectors and the volts are still low, so I dont think is a card fault and it's probably a PSU fault. The 0.3 ohm resistor in the +15v line says its has a draw of 1.0 amps with seems a lot at 4 volts though.

the +/- 17v rails that feed the +/- 15v are fine.

I would have suspected s/c Tants, but there does not seem to be any tants.

Any help welcomed please.

I've included a part of the circuit with some voltages on.

Thanks Nick G0HIK


Re: Help with Tektronixs 492 S.A. PSU fault.

Ian White
 

Nick,

Would an 2x18-way double sided board extender be any use, 0.15in pitch and about 5in long? Could post it on Monday.

A batch was made some years ago for working on FT221 RF boards, so if you really need two there may still be others around to borrow.

73 from Ian GM3SEK


On 15/01/2021 20:49, Nick Gregory G0HIK via groups.io wrote:

Thanks, But unfortunately not this time.

It's a right pain soldering wires to various test points to bring them to the outside would.

I think you can still get 0.15" ( I think) PCB sockets, can you obtain the mating double sided PCB to make a couple of extenders ?

1781 - 1800 of 62213