Re: HP 8116A woes with E42 error
On Mon, May 30, 2022 at 03:27 PM, Swiss wrote:
1) anode of CR501 = -7.891 Vdc
2) emitter of Q501 = -1.0263 Vdc
3) cathode of CR502 = -9.446 Vdc
4) emitter of Q502 = 1.0324 Vdc
5) top of R511 (node 47) = .0024 Vdc
The combination of 3) and 4) would indicate Q502 has open base-emitter. Raymond
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Re: servicing 8671B Synthesized CW Generator 2.0-18 Ghz unit (first power up)
First red flag is the missing seal on the top screw which indicates someone been in there before .
The phaselock message normally clears once the unit warms up but it could also be a indication of a more serious issue
First thing I do is to pop the top lid and do a visual if you see any missing parts, disconnected cables , missing screws etc ,? next check your power supply rails ,? I don’t remember if the 8672 has it but in a lot of units HP put LEDs
on the regulator boards so you can see quickly if any voltage is missing ,? you can find the service guide online which contains schematics and measure the supply voltages to see if everything is there .
If the power supplies are ok the next thing to check is the YTO and YTO driver ,? the 8672 uses a 2-6GHz YIG that is fed into a power amplifier and then a YTM ,? disconnect the YTO and connect a power meter or spectrum analyzer but be sure
to add a 20Db pad because the YTO produces quite a bit of power ,? if the YTO has no output check the Current though the tuning coil .
YIGs unlike VCOs only oscillate if the resonator is tuned to a frequency within the operating range ,? the resonator is tuned by a magnetic field produced by a coil so if the coil has insufficient or no current you wont see any output .
If there is no current more than likely you have a issue with the driver circuit .
If the YTO has output then you need to check the power amplifier and if this is ok check the YTM .
The YTM is in essence a multiplier with a YIG filter that multiplies the 2-6GHz Signal to 6-18GHz , once again it could be a driver issue as the YTM has a driver too or the YTM could be bad which is the worst case .
?
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From: [email protected] < [email protected]>
On Behalf Of Samudra via groups.io
Sent: Monday, May 30, 2022 1:33 PM
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] servicing 8671B Synthesized CW Generator 2.0-18 Ghz unit (first power up)
?
Hello Lothar and HAKE community I? just got cables shipped to me, and planned to use a semi rigid microwave test cable for early check? out between 8671b generator and 8566b spectrum analyzer.?
I had a feeling the 8671b? ?would not work as output? meters did not move? and can now? confirm that the set seems to not produce RF output or if it does the left side display panel is quiet. See picture?attached.?
When I depress the preset 2Ghz button, range display is showing -110 to +10 dBm but with RF output to on, ALC and RF display is blank, NOT PHASE LOCKED sign is on and that's it.?
Any general servicing checks I can do ? As I am not exactly moved in to my new apartment I won't have time to do a detailed breakdown until next month. I do have other signal generator and my work involves designing a new board so if this
unit does not ever work it's not a big deal but still would like to know what I can do. The unit was purchased from a personal estate liquidator and was in unknown condition when I picked it up.
?I checked the rear connectors and both 10 MHz and 100 MHz ref outputs are producing signal. Seen using 8342a counter.?
Not much in the rear panel, so wondering if this is a case of bad components or loose module connections.? The unit had been mishandled during shipping several times.
?
On Tue, May 24, 2022, 00:09 Lothar baier <Lothar@...> wrote:
Generally use the distribution amplifier outputs it’s the best way to do it and also make sure to terminate the unused outputs !
As far as the 8671B concerns, turn on the unit and let it warm up,? make sure the ALC switch is set to INT , Set the RF Switch to ON , use the big knob to set the range to 0dBm
and the vernier knob to set the meter to read 0dBm , there should be no annunciator be on except the ALC INT and RF ON , connect the power meter to the RF Output and your power meter should read 0dbm ,? change the range to 10dBm , your unlevel light may come
on if so reduce the level using the vernier knob to 8dBm or less ( the spec for the 8671B is 8dBm if I remember correctly ) , your power meter should agree with the meter in the 8671B within about 1Db or so however consider that this generation of generators
is not as accurate as later model generators such as the 8360 series or PSG !
?
?
Hi, I recently cheaply (< $700) acquired working (they power on) set from a deceased engineer's estate sale in the US:
-
HP 8566B 100 Hz - 22 GHz spectrum analyzer (two sections)?
-
HP 8671B CW Synthesized Generator (2-18 GHz)
I have used HP/Keysight/Agilent systems in labs before, but this time these are "mine" :-)? I also have a (nicely serviced and working) HP 5342A Microwave Frequency counter, that should
be good to 18 GHz, and I want to experiment (I am a ham radio operator, engineer) with RF signals for TX, RX by designing a few PCBs using microwave semiconductors, FPGA etc.,?
I also have coming soon to my home lab a GPS disciplined oscillator, 10 MHz OCXO ref, with a single output, but from another project I have a unity-gain 16-bank (1 in, 4 output) BNC video distribution panel,
which if all sixteen (16) inputs were utilized, would produce 64 outputs. So, can I ask in general for some assorted configuration tips please?
-
When the CW Generator is turned on,after warm up, what is the procedure to check if the power meter (left side) is functional? the right side does power up with illuminated symbols - and frequency adjustment can be done manually, but what about the left side,
what should I be seeing to verify functionality - other than RF produced that can be "seen" in the spectrum analyzer - I know that unit works.?
-
Assuming I want to distribute 10 Mhz clock, ;is distributing the master clock ref via BNC T-connectors? worse than individual lines from the unity amplifier bank??
-
Assuming a single 10 MHz clock distributed: how do I verify "correct operation" of the Spec. An + CW Generator + Frequency Counter ? What are the go/no-go tests??
-
I want to use automation to record and run tests - and have an available LINUX workstation in the same rack with PCI-E x1 and x16 slots available. Any tips on LINUX GPIB etc? Is a GPIB-USB better than GPIB-Ethernet for accessing multiple machines? Any horror
stories? How is the support in LINUX compared to Windows 10/11 nowadays for GPIB users who don't have NI toolsets yet?
-
is earthing a big deal between the units if they are fed from the same power distribution unit on a single phase??
Thanks for your time. For convenience I have numbered the questions above. Didn't want to create too many topics on this first day of joining this group.?
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Re: E4418B power supply schematic?
Hi Tom,
Thanks for the datasheet. I saved it for next time.
This time I got lucky - another one of those resistors was open. It was the same value as the one I replaced several years ago, so I still had some spares.
The standby light was off.
Cheers,
Razvan
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On 30/05/2022 20:27, Tom B wrote: Hi Razvan,
I don't have a schematic, but mine has an Artesyn NFN40-7608. The datasheet is here.
Is the standby light on, or do you get nothing?
Tom
On 5/30/2022 10:49 AM, Razvan wrote:
Hey everyone,
Is there any information out there on the power supply used in these units? Mine appears to have died (I can't measure any output), and I can't find the schematic in the CLIP files.
The full part number of the PSU seems to be JW 1287, JW being the manufacturer.
This isn't the first time it failed. Many years ago a resistor went open, but I don't remember how I troubleshooted that, and I didn't take any notes...
Cheers,
Razvan
|
I sounds like there may be a problem with the reverse power protection.? There are PIN diodes in series with zener diodes to ground in the protection circuit and it sounds like perhaps one of the zeners has shorted out - probably from application of reverse power above the specification.?
If you were to look at the signal at the input to the attenuator and you see no distortion at high levels (+10dBm and above) then it is probably the reverse power protection circuitry that is at fault...? It is the first thing seen coming in from the front panel connector and I believe it is in one of the attenuator enclosures.?
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Re: servicing 8671B Synthesized CW Generator 2.0-18 Ghz unit (first power up)
Hello Lothar and HAKE community I? just got cables shipped to me, and planned to use a semi rigid microwave test cable for early check? out between 8671b generator and 8566b spectrum analyzer.?
I had a feeling the 8671b? ?would not work as output? meters did not move? and can now? confirm that the set seems to not produce RF output or if it does the left side display panel is quiet. See picture?attached.?
When I depress the preset 2Ghz button, range display is showing -110 to +10 dBm but with RF output to on, ALC and RF display is blank, NOT PHASE LOCKED sign is on and that's it.?
Any general servicing checks I can do ? As I am not exactly moved in to my new apartment I won't have time to do a detailed breakdown until next month. I do have other signal generator and my work involves designing a new board so if this unit does not ever work it's not a big deal but still would like to know what I can do. The unit was purchased from a personal estate liquidator and was in unknown condition when I picked it up.
?I checked the rear connectors and both 10 MHz and 100 MHz ref outputs are producing signal. Seen using 8342a counter.?
Not much in the rear panel, so wondering if this is a case of bad components or loose module connections.? The unit had been mishandled during shipping several times.
Thank you.?
On Tue, May 24, 2022, 00:09 Lothar baier < Lothar@...> wrote:
Generally use the distribution amplifier outputs it’s the best way to do it and also make sure to terminate the unused outputs !
As far as the 8671B concerns, turn on the unit and let it warm up,? make sure the ALC switch is set to INT , Set the RF Switch to ON , use the big knob to set the range to 0dBm and the vernier knob to set the meter to read 0dBm , there
should be no annunciator be on except the ALC INT and RF ON , connect the power meter to the RF Output and your power meter should read 0dbm ,? change the range to 10dBm , your unlevel light may come on if so reduce the level using the vernier knob to 8dBm
or less ( the spec for the 8671B is 8dBm if I remember correctly ) , your power meter should agree with the meter in the 8671B within about 1Db or so however consider that this generation of generators is not as accurate as later model generators such as the
8360 series or PSG !
?
?
Hi, I recently cheaply (< $700) acquired working (they power on) set from a deceased engineer's estate sale in the US:
-
HP 8566B 100 Hz - 22 GHz spectrum analyzer (two sections)?
-
HP 8671B CW Synthesized Generator (2-18 GHz)
I have used HP/Keysight/Agilent systems in labs before, but this time these are "mine" :-)? I also have a (nicely serviced and working) HP 5342A Microwave Frequency counter, that should be good to 18 GHz, and
I want to experiment (I am a ham radio operator, engineer) with RF signals for TX, RX by designing a few PCBs using microwave semiconductors, FPGA etc.,?
I also have coming soon to my home lab a GPS disciplined oscillator, 10 MHz OCXO ref, with a single output, but from another project I have a unity-gain 16-bank (1 in, 4 output) BNC video distribution panel,
which if all sixteen (16) inputs were utilized, would produce 64 outputs. So, can I ask in general for some assorted configuration tips please?
-
When the CW Generator is turned on,after warm up, what is the procedure to check if the power meter (left side) is functional? the right side does power up with illuminated symbols - and frequency adjustment can be done manually, but what about the left side,
what should I be seeing to verify functionality - other than RF produced that can be "seen" in the spectrum analyzer - I know that unit works.?
-
Assuming I want to distribute 10 Mhz clock, ;is distributing the master clock ref via BNC T-connectors? worse than individual lines from the unity amplifier bank??
-
Assuming a single 10 MHz clock distributed: how do I verify "correct operation" of the Spec. An + CW Generator + Frequency Counter ? What are the go/no-go tests??
-
I want to use automation to record and run tests - and have an available LINUX workstation in the same rack with PCI-E x1 and x16 slots available. Any tips on LINUX GPIB etc? Is a GPIB-USB better than GPIB-Ethernet for accessing multiple machines? Any horror
stories? How is the support in LINUX compared to Windows 10/11 nowadays for GPIB users who don't have NI toolsets yet?
-
is earthing a big deal between the units if they are fed from the same power distribution unit on a single phase??
Thanks for your time. For convenience I have numbered the questions above. Didn't want to create too many topics on this first day of joining this group.?
|
Re: E4418B power supply schematic?
Hi Razvan,
I don't have a schematic, but mine has an Artesyn NFN40-7608. The datasheet is here.
Is the standby light on, or do you get nothing?
Tom
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On 5/30/2022 10:49 AM, Razvan wrote: Hey everyone,
Is there any information out there on the power supply used in these units? Mine appears to have died (I can't measure any output), and I can't find the schematic in the CLIP files.
The full part number of the PSU seems to be JW 1287, JW being the manufacturer.
This isn't the first time it failed. Many years ago a resistor went open, but I don't remember how I troubleshooted that, and I didn't take any notes...
Cheers,
Razvan
|
According to the manual on the Keysight site, 08562-90124 should be a complete set of the 'latest' CLIPs.? The CLIP for A4 2923A prefix should be 08562-90128.? You'd have to ask Dave at Artek whether his copy of '124 includes it as Keysight's manual also says "CLIPs may not be available for recently introduced assemblies". Whether this would help is a different matter as the same manual essentially says A4 is factory only repair.
On Mon, May 30, 2022 at 8:56 AM hardyhansendk via <hardyhansen= [email protected]> wrote:
Hi Richard
Artek have the? 08562-90124 CLIP.
Hardy
?
?
Hi All I'm Looking for a HP service manual for the 8562A but
not the one that seems commonly available (08562-90062 for serial number prefix
2913A) my serial number is 2923A, I'm looking at the log amp detector and the
trouble shooting? seems completely wrong so I suspect there has been
changes, If anyone has prefix 2923A or later or could point me in the right
direction i would be grateful, thanks
|
Hi Richard
Artek have the? 08562-90124 CLIP.
Hardy
?
?
Hi All I'm Looking for a HP service manual for the 8562A but
not the one that seems commonly available (08562-90062 for serial number prefix
2913A) my serial number is 2923A, I'm looking at the log amp detector and the
trouble shooting? seems completely wrong so I suspect there has been
changes, If anyone has prefix 2923A or later or could point me in the right
direction i would be grateful, thanks
|
Hi All I'm Looking for a HP service manual for the 8562A but not the one that seems commonly available (08562-90062 for serial number prefix 2913A) my serial number is 2923A, I'm looking at the log amp detector and the trouble shooting? seems completely wrong so I suspect there has been changes, If anyone has prefix 2923A or later or could point me in the right direction i would be grateful, thanks
|
E4418B power supply schematic?
Hey everyone,
Is there any information out there on the power supply used in these units? Mine appears to have died (I can't measure any output), and I can't find the schematic in the CLIP files.
The full part number of the PSU seems to be JW 1287, JW being the manufacturer.
This isn't the first time it failed. Many years ago a resistor went open, but I don't remember how I troubleshooted that, and I didn't take any notes...
Cheers,
Razvan
|
HP 8662A - alternative attenuator configurations
Hi,
While trying to fix my HP8662A I'm trying to work out if?it is missing an output attenuator relay drive cable - or not.
There appear to be at least two attenuator configurations in these instruments. My machine has two attenuator units, each with a ribbon cable attached - which I assume are the relay drive signals. I have seen pictures of other revs of the instrument with a single larger attenuator with a drive cable that comes from the motherboard, but no ribbon cables. I attach a picture of both configs, as far as I can research them.
I can't find any HP update/change documentation on the internet about when the configuration of the attenuators for this instrument changed - or indeed, if it is an instrument option.
My question regards the attenuator drive cable. In my own instrument with 2 attenuators there is no drive cable plugged in to the motherboard (see circled area in pictures). In the single attenuator model this cable exists (again, see picture). So should my instrument have that cable (i.e. it is missing), or do the ribbon cables carry those signals and therefore does not need one?
I hope that is clear!
Many thanks
Tony
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Re: HP 8116A woes with E42 error
With the offset is set to -2.00 Vdc, the output of U502 reads -13.240.
1) anode of CR501 = -7.891 Vdc
2) emitter of Q501 = -1.0263 Vdc
3) cathode of CR502 = -9.446 Vdc
4) emitter of Q502 = 1.0324 Vdc
5) top of R511 (node 47) = .0024 Vdc
Thanks,
David
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Re: HP 8116A woes with E42 error
On Sun, May 29, 2022 at 09:21 PM, Swiss wrote:
...
U501 they call an offset current compensation amplifier, and U502 they call the offset voltage control. I measured the output of both U501 and U502 at different offset output settings, and here are the results,
U501
-7 Vdc = 9.037
-5 Vdc = 9.014
-2 Vdc = 8.990
0 Vdc = 8.749
20 mVdc = -.0906 <-- I included this because of the results I was seeing from U502
1 Vdc = -2.0732
2 Vdc = -3.3286
5 Vdc = -6.935
7 Vdc = -9.305
U502
-7 Vdc = -13.526
-5 Vdc = -13.256
-2 Vdc = -13.252
0 Vdc = -13.252
20 mVdc = -13.123 <-- At approximately 28 mV, the output changes from -13.123 V to -0.7800??
1 Vdc = -.6912
2 Vdc = -.6774
5 Vdc = -.6600
7 Vdc = -.6544
------ When offset is set to one of the settings that produce -13.2V at the output of U502, what voltages do you measure at 1) anode of CR501? 2) emitter of Q501? 3) cathode of CR502 4) emitter of Q502 5) top of R511 (node 47) Ozan
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Re: HP 8116A woes with E42 error
So I did some more reading and I was wondering what comes after the DAC output control from A2. As mentioned before, I measured the output of the DAC and listed the voltages in my first post. They were slightly out of spec according to the repair manual, but not so much that I was concerned about it. I kept following the trail and ended up at U501 and U502.
U501 they call an offset current compensation amplifier, and U502 they call the offset voltage control. I measured the output of both U501 and U502 at different offset output settings, and here are the results,
U501
-7 Vdc = 9.037
-5 Vdc = 9.014
-2 Vdc = 8.990
0 Vdc = 8.749
20 mVdc = -.0906 <-- I included this because of the results I was seeing from U502
1 Vdc = -2.0732
2 Vdc = -3.3286
5 Vdc = -6.935
7 Vdc = -9.305
U502
-7 Vdc = -13.526
-5 Vdc = -13.256
-2 Vdc = -13.252
0 Vdc = -13.252
20 mVdc = -13.123 <-- At approximately 28 mV, the output changes from -13.123 V to -0.7800??
1 Vdc = -.6912
2 Vdc = -.6774
5 Vdc = -.6600
7 Vdc = -.6544
U502 feeds the inputs of Q501 and Q502. It doesn't look like U502 is working properly to me. All the components surrounding U502 look in good shape and measure fine as well.
I thought about injecting variable DC into the input of R509 to see if I would get a different response, but I decided against that as I didn't want to subject the output of another function generator or the input of the amplifier without breaking the circuit. U502 is an OP-07CP an they are readily available. I ordered a couple. In the mean time, (tomorrow if I am able) I may remove U502 and try injecting a signal into the system to see if it the culprit, or I may open the other unit I have, and compare measurements.?
I'm still not 100% sure if this is the trouble spot, but it looks to be very suspect.
Thanks,
David
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Re: 53181A 3 GHz prescaler from China
Has anyone measured the additional phase noise from this clock multiplier module, or others?
Thanks, Ron
-
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Re: Limits of the Port Extension on the Cal screen for calibrating at end of cable
Not sure if this has been mentioned, and it is entirely academic, but the attenuation of the cable could degrade accuracy if the cables have significant enough loss.? However with your cable (RG213), length (100ft) and freq (14MHz) this loss is small. and?will not make a significant difference.
If you pushed the frequency up into the GHz, then it could be significant. Cable loss will eat into the available dynamic range of the return loss calculations, and if there is enough loss then the mathematical precision and instrument stability will start to limit measurement accuracy.
i.e. with enough loss, then the signal reflected back to the VNA by the open/short and the zero reflection for the load will start to look the same.
Cheers, Roger
On Sat, 28 May 2022, 11:50 AM Karin Johnson, < karinann@...> wrote: I realized a couple of hours after sending the initial post, that I was incorrect with associating Calibration with the Port Extensions.
Here is, I hope a better explanation of what I am trying to do.
First off the measurement frequency is 14 MHz.? So not too beyond the capability of the 8753C.
I want to place the measurement plane at the end of a 100 foot length of RG213.? So I place the SOL standards, one at a time at the
end of the cable.? Supposedly the 8753C measurement plane is now at the end of the cable.
Now I can take S11 measurements relative to the measurement plane at the end of the cable.? My question should have been
" Is there a limit in terms of how long a cable can be before this calibration technique fails."
This is probably related to the storage of the cal correction factors in the memory of the 8753C.? Is it via floating point numbers, or integer numbers?
How large or small can the calibration correction values be???
I seem to be able to obtain valid data using this technique, but wanted to ask on the Keysight forum with some of the folks who actually designed
the instrument.? I think Dr. Joel it still active there.?
My rant about not being able to login to the Keysight forums still exists.? It seems their login/validation screen seems broken.
At one time I had an account over there but they have seemed to have changed the supporting vendor for the forum sites.
As always,
Regards,
Karin Johnson
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Re: Limits of the Port Extension on the Cal screen for calibrating at end of cable
Thanks to all who replied.
I used to design fiber optic systems, among my other system design tasks, and am aware of the fact the receiver cannot sometimes track the source because of long delays in the cable or fiber.? I have slowed the sweep and have not noticed any appreciable discrepancies with the data.? So my conclusion is that using a 30 Meter (my tip of the hat to Dr, Kirkby) cable should enact the calibration, and would not be an issue for the 8753C.? I agree with Tom about only the phase being a factor in the port extensions.? But I am not using port extensions.? I have a piece of software that will allow me to enter data for measurements taken at various points along a fixed length of cable, and can "BACk OUT" the cable to reflect the actual data at the calibration plane.
All of that experimentation with that software and real world measurements seem to correlate correctly.??? This question from the very beginning, excepting my original mistake, was somewhat academic.? I have been using this method for a number of years and it does work.?
I guess recently I've become a bit bored looking for some new project to undertake.
I truly respect the groups knowledge and time putting up with my questions.
Regards,
Karin
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Re: HP8563E-Damaged red coax from A4 PCB-Is it easy to replace?
According to the CLIP the A4 assembly is the Log Amp and Cal assembly. J3,J4,J5,J7 and J8 are 50 Ohm SMB connectors according to the parts list. I have not identified the EXACT designation of the RED SMB coaxial lead in question yet. I'll have a look next weekend.
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Re: HP8563E-Damaged red coax from A4 PCB-Is it easy to replace?
A few comments on SMB connectors :
SMB is a push on RF connector that is a cousin of the SMC connector both are identical except of the SMC being screw on.
SMB was designed as a miniature RF connector for internal wiring , it is normally used with RG174,188 and 316 cables but there are also versions that accommodate 0.086 hardline.
Frequency rating is -4GHz although in testing equipment it’s usually used below 1GHz mostly for IF or sweep signals .
The biggest concern with SMB is that like most push ons they are leaky and tend to develop reliability issues over time as the leaf springs holding the connector in place tend to lose tension.
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On May 29, 2022, at 13:23, David via groups.io <david@...> wrote:
?George,
I will confirm if there is a connector on the other end and the exact length this coming weekend. Thank you.
David.
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Re: HP8563E-Damaged red coax from A4 PCB-Is it easy to replace?
What is the signal involved? HP often used SMB for DC bias or things
like RF detector outputs when they just wanted a well screened
cable. If that is the case here then a slightly squidged cable is
not a problem (assuming it still has continuity and isn't shorted of
course!)
On 29/05/2022 18:58, David wrote:
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Thank you for your replies so far.
Please find attached a photo of the connectors and the damaged
coax cable (Red). If I was to buy cable it is important to buy the
correct type so that it's the correct impedance and also so that
it fits any connector properly. I hope you can help me further.
Thanks
Attachments:
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Richard
