Date   

Re: Anyone got any spare WG15 / WR112 waveguide

Andy G4JNT
 

I think I'd be more inclined to look at WG14 for that rather than WG15.

At 3.4GHz WG16 was at about the limit that could be used, screw penetration was nearly right across the guide - although it worked very well indeed, and I've made three repeatable units for that band.  http://g4jnt.com/EVANFILT.pdf

Looking at dimensions, linear scaling suggests WG14 wouldn't be too far off the mark

It would be nice to get a filter that covers 2300 - 2420 with a good transition band - especially on the LF side for image rejection.   SO may be worth looking at a 4th order design.  
Evanescent filters are so easy to throw together, and drilling too many tapped holes while just playing around wont hurt the final result.



On Fri, 29 Jan 2021 at 21:35, g4cch_1 <g4cch_1@...> wrote:
I'm looking for a short length of WG15 WR112 to make an evanescent mode filter for 13cm

If anyone has some to spare, please email me off line.

Thanks and 73
Howard, G4CCH


Re: MEMS switches

Robin Szemeti - G1YFG
 

What sort of frequency range, power level? You can always just ignore the extra pins ...

I have been using the "Skytronics" T/R switch SKY13330-397LF  seems to work fine in my application.  This is a 12 pin device, but implements the traditional T/R switch with low loss and simple control.  £0.70 from Mouser.


They do higher power stuff too:


What is nice about that Menlo device is it is an actual teeny-weeny mechanical switch. That's pretty amazing technology when you think about it!


On Sat, 30 Jan 2021 at 05:04, Greg - ZL3IX <zl3ix@...> wrote:
These were mentioned by Andy JNT in his Design Ideas for the Dec RadCom.

I looked on the Menlo web site but only see 3 devices, all of them more complex than the SPDT we normally need for amateur designs. Does anyone know of any similar, but simpler, devices? Also any idea of price?


--
Robin Szemeti - G1YFG


MEMS switches

Greg - ZL3IX
 

These were mentioned by Andy JNT in his Design Ideas for the Dec RadCom.

I looked on the Menlo web site but only see 3 devices, all of them more complex than the SPDT we normally need for amateur designs. Does anyone know of any similar, but simpler, devices? Also any idea of price?


Re: round attenuator dissasembly?

Andy G4JNT
 

Even back in the 1970s - 80s they were making a big fuss about it.   My Mother was an occupational health nurse at the old Austin-Rover Longbridge plant and I remember her talking about the Beryllia kit they had on standby.   Quite where the substance would have been used in the motor industry I don't know, but she certainly got all perturbed seeing the "Warning Contains BeO" sign on one of my packages. 

Andy


On Fri, 29 Jan 2021 at 21:46, Graham G3VKV via groups.io <g3vkv=btinternet.com@groups.io> wrote:
Ben,
I would read this instead only 166 pages -  and look on the auction site for a new attenuator.

Communicating Health Risks Working Safely with Beryllium (energy.gov)

Graham G3VKV


Re: round attenuator dissasembly?

Graham G3VKV
 

Ben,
I would read this instead only 166 pages -  and look on the auction site for a new attenuator.

Communicating Health Risks Working Safely with Beryllium (energy.gov)

Graham G3VKV


Anyone got any spare WG15 / WR112 waveguide

g4cch_1
 
Edited

I'm looking for a short length of WG15/WR112 to make an evanescent mode filter for 13cm

If anyone has some to spare, please email me off line.

Thanks and 73
Howard, G4CCH


Re: F6BVA 10 GHz transverter PCB group order

Neil Smith G4DBN
 

All boards are spoken for now sorry. I've started a waiting list for any cancellations, and Pierre-François may order a new batch in a month or two. If you are interested but missed out, please feel free to email with your requirements and I'll add you to the waiting list and let you know when more boards are available. Feel free to join the IO group, which I still have to configure, but it does seem to have been approved at last.  I'll send invites to everyone who has made a request, and put the details on here for anyone interested in the project.

Neil G4DBN


Re: F6BVA 10 GHz transverter PCB group order

David Minchin
 

Hi Neil

If that last board is still free I will take it!

Cheers

David VK5KK 


Re: F6BVA 10 GHz transverter PCB group order

G1BVI-Nick
 

Hi Neil
Cannot see my first message
Can you put me down for a board please#Thanks
73
Nick
G1BVI


Re: round attenuator dissasembly?

militaryoperator
 

Ben,
I could be wrong , but when I opened up an O/C inline 1W rated pad from a junk bin  I found the sputter deposited /laser trimmed resistive elements had more or less vapourised .
However the R was deposited on thin ceramic substrate and that was retained along the long edges with what looked like Beryllium foil .Very tight /more or less impossible to get out without cracking the ceramic .
So basically do not cut/file or swallow the foil bits and you should live to enjoy the RF 'speriments you are doing .
73
John
G0API



Sounds exactly the same as this one John. 

I have kept the gold edge trimmings, I thought I might be able to make a replacement slice, maybe with cutouts and sma R's inserted etc. 

Give me something to do whilst going up the walls. 

Ben G4BXD


Re: F6BVA 10 GHz transverter PCB group order

Neil Smith G4DBN
 

Slightly gobsmacked, and I suspect there will be more requests, but Pierre-François wanted to get the groupire closed off and the order sent to the fab.  There will probably be another group buy in a few months (this is their seventh group buy for the F6BVA transverter I think). There are often really good group buy projects on hyperfr and hyper-ref. 


I expect some questions about local oscs, antenna feeds, enclosures, LANs, relays and PAs, so things could get interesting.  I'll get a BOM put together in case anyone want to join a group buy from Digikey/Mouser, also I'd better give a heads-up to Alan G3NYK about tinplate boxes and find a decent source of self-adhesive RF absorbent stuff.


Fifty seemed like such a huge number when I plucked it out of the air this morning.


All of this from a daft whim on Wednesday.  Madness.


Neil G4DBN


On 29/01/2021 17:19, Andy wrote:
Bet you didn't expect that number? I didn't 🙂



Re: F6BVA 10 GHz transverter PCB group order

Andy
 

Bet you didn't expect that number? I didn't 🙂

Thank you for doing this Neil.

Andy


From: UKMicrowaves@groups.io <UKMicrowaves@groups.io> on behalf of Neil Smith G4DBN <neil@...>
Sent: Friday, January 29, 2021 9:11 AM
To: UKMicrowaves@groups.io <UKMicrowaves@groups.io>
Subject: Re: [UKMicrowaves] F6BVA 10 GHz transverter PCB group order
 

The French group purchase is closed, but I ordered a sneaky few extra boards for stragglers.  However, only ONE of the batch of 50 I ordered is still unsold. Apologies if anyone misses out, I was VERY late to the game but didn't want to pony up vast amounts of cash for boards that were not going to sell, and 50 seemed a ludicrously high number. I am amazed.

If you made an order and you aren't in this list, or if I got the quantity wrong, or you want to cancel or reduce your order, please yell now.

I will be sending out invitations tonight to join a new IO group which I'll use to manage the orders and where we can discuss sourcing components and tips and tricks and illuminate any language issues with the build documentation.  I'll put a note on here when it happens. 

I'm sure folks will want to discuss choice of LOs, PAs, LNAs, relays and enclosures, but much of that is better done on this group, where the full audience will be reached.

Neil G4DBN

Call PCBs Components
GI0GDP 2  
G4GLT 1  
G8AFC 2  
G0UHY 2  
G1YFG 1  
G4LDR 1  
G4DBN 5 5 x full sets
G3ZQU 1  
G8JVM 1  
G3LYP 1 1 x FETs and Mixer
G4KNZ 1 1 x full set
G4DZU 1  
G3YGF 1  
GM8GAX 1  
G3GJA 2  
G4SHJ 1  
G7SOZ 1  
VE7HR 3  
G0OLX 1  
MM0FMF 1  
G6KWA 1  
G4IDR 1 1 x Full set
M0EYT 1  
M0KDS 1  
G8LBS 1  
M0TEU 2  
M0RVB 1  
G3YKI 1  
G6TRM 1  
GM0KZX 1  
VK6KW 2  
G8GTZ 1  
G8KHU 3  
M0BPQ 2  



































































































From: UKMicrowaves@groups.io <UKMicrowaves@groups.io> On Behalf Of Neil Smith G4DBN

Sent: 28 January 2021 21:48
To: UKMicrowaves@groups.io
Subject: Re: [UKMicrowaves] F6BVA 10 GHz transverter PCB group order

 

Sorry for the short notice, but Pierre-François is likely to close this group buy tomorrow, so if you would like to order some PCBs, please say so quickly! 

Don't worry about the components part of the order, plenty of time to sort that out, just let me know if you want a PCB. The price will probably fall a little as the volume increases, but the likely price is somewhere around £30 if we get stung for VAT and carrier ransom fee and duty. If Royal Mail are still operating by the time the boards arrive, I'll post them out first class large unless you are in one of the areas where they have given up trying, but again, we can sort that later on.

Details are at https://f6bva.pagesperso-orange.fr/Technique/trans%20uhf%20vers3cm/dossier%20print%20Ag%20complet.pdf

Once the boards arrive, I'll contact you for delivery info and let you know the final cost. Paypal or bank transfer or cheque are fine

Remember you need to provide a suitable local osc.  Read the info and the link that Daniel posted earlier. As mentioned, if you are not up to speed in French tech abbreviations, CI = PCB, CMS = SMD, OL = LO

This is the order so far. If I've missed you off or got the number wrong, or you need to change/cancel, please let me know before tomorrow night

Neil G4DBN

On Thu, Jan 28, 2021 at 12:35 AM Neil Smith G4DBN <neil@...> wrote:
If anyone in the UK is considering building an F6BVA 3cm to UHF transverter, there is a group purchase under way for the PCBs. To save on carrier fees, I am happy to receive boards for other UK purchasers and post them onwards. 

I have ordered three for myself. Price for the last batch worked out at 23€ plus postage, that was for 30 boards. There will be VAT, local postage, a share of the carrier fee and processing, and potentially UK duty to be paid (the silver plated PCBs are from a Chinese fab) so the final UK price might be over £30 each.

Read the updated tech info in the link below, and the earlier versions it links to. If you are not able to read technical French and rely on Google Translate, remember CI = PCB, OL = LO, CMS = SMD.

Neil G4DBN


From: f5bqp_Pierre-François MONET <pfmonet@...>
Subject: [hyperfr@...] Mise à jour de la Groupire CI Trvt 3cmBVA_batch7
Date: 27 January 2021 at 20:52:24 GMT
Resent-From: pfmonet@...
Bonjour,

La Groupire batch7 du CI du transverter 10GHz avance tout doucement puisque 18 exemplaires sont maintenant inscrits.
Le descriptif est ici:
https://f6bva.pagesperso-orange.fr/Technique/trans%20uhf%20vers3cm/dossier%20print%20Ag%20complet.pdf

_


Re: F6BVA 10 GHz transverter PCB group order

Neil Smith G4DBN
 

The French group purchase is closed, but I ordered a sneaky few extra boards for stragglers.  However, only ONE of the batch of 50 I ordered is still unsold. Apologies if anyone misses out, I was VERY late to the game but didn't want to pony up vast amounts of cash for boards that were not going to sell, and 50 seemed a ludicrously high number. I am amazed.

If you made an order and you aren't in this list, or if I got the quantity wrong, or you want to cancel or reduce your order, please yell now.

I will be sending out invitations tonight to join a new IO group which I'll use to manage the orders and where we can discuss sourcing components and tips and tricks and illuminate any language issues with the build documentation.  I'll put a note on here when it happens. 

I'm sure folks will want to discuss choice of LOs, PAs, LNAs, relays and enclosures, but much of that is better done on this group, where the full audience will be reached.

Neil G4DBN

Call PCBs Components
GI0GDP 2  
G4GLT 1  
G8AFC 2  
G0UHY 2  
G1YFG 1  
G4LDR 1  
G4DBN 5 5 x full sets
G3ZQU 1  
G8JVM 1  
G3LYP 1 1 x FETs and Mixer
G4KNZ 1 1 x full set
G4DZU 1  
G3YGF 1  
GM8GAX 1  
G3GJA 2  
G4SHJ 1  
G7SOZ 1  
VE7HR 3  
G0OLX 1  
MM0FMF 1  
G6KWA 1  
G4IDR 1 1 x Full set
M0EYT 1  
M0KDS 1  
G8LBS 1  
M0TEU 2  
M0RVB 1  
G3YKI 1  
G6TRM 1  
GM0KZX 1  
VK6KW 2  
G8GTZ 1  
G8KHU 3  
M0BPQ 2  



































































































From: UKMicrowaves@groups.io <UKMicrowaves@groups.io> On Behalf Of Neil Smith G4DBN

Sent: 28 January 2021 21:48
To: UKMicrowaves@groups.io
Subject: Re: [UKMicrowaves] F6BVA 10 GHz transverter PCB group order

 

Sorry for the short notice, but Pierre-François is likely to close this group buy tomorrow, so if you would like to order some PCBs, please say so quickly! 

Don't worry about the components part of the order, plenty of time to sort that out, just let me know if you want a PCB. The price will probably fall a little as the volume increases, but the likely price is somewhere around £30 if we get stung for VAT and carrier ransom fee and duty. If Royal Mail are still operating by the time the boards arrive, I'll post them out first class large unless you are in one of the areas where they have given up trying, but again, we can sort that later on.

Details are at https://f6bva.pagesperso-orange.fr/Technique/trans%20uhf%20vers3cm/dossier%20print%20Ag%20complet.pdf

Once the boards arrive, I'll contact you for delivery info and let you know the final cost. Paypal or bank transfer or cheque are fine

Remember you need to provide a suitable local osc.  Read the info and the link that Daniel posted earlier. As mentioned, if you are not up to speed in French tech abbreviations, CI = PCB, CMS = SMD, OL = LO

This is the order so far. If I've missed you off or got the number wrong, or you need to change/cancel, please let me know before tomorrow night

Neil G4DBN

On Thu, Jan 28, 2021 at 12:35 AM Neil Smith G4DBN <neil@...> wrote:
If anyone in the UK is considering building an F6BVA 3cm to UHF transverter, there is a group purchase under way for the PCBs. To save on carrier fees, I am happy to receive boards for other UK purchasers and post them onwards. 

I have ordered three for myself. Price for the last batch worked out at 23€ plus postage, that was for 30 boards. There will be VAT, local postage, a share of the carrier fee and processing, and potentially UK duty to be paid (the silver plated PCBs are from a Chinese fab) so the final UK price might be over £30 each.

Read the updated tech info in the link below, and the earlier versions it links to. If you are not able to read technical French and rely on Google Translate, remember CI = PCB, OL = LO, CMS = SMD.

Neil G4DBN


From: f5bqp_Pierre-François MONET <pfmonet@...>
Subject: [hyperfr@...] Mise à jour de la Groupire CI Trvt 3cmBVA_batch7
Date: 27 January 2021 at 20:52:24 GMT
Resent-From: pfmonet@...
Bonjour,

La Groupire batch7 du CI du transverter 10GHz avance tout doucement puisque 18 exemplaires sont maintenant inscrits.
Le descriptif est ici:
https://f6bva.pagesperso-orange.fr/Technique/trans%20uhf%20vers3cm/dossier%20print%20Ag%20complet.pdf

_


Re: F6BVA 10 GHz transverter PCB group order

Steve Bunting M0BPQ
 

Hi Neil,

Two PCBs for me please! Interested in components too at a later date.

Thanks for doing this.

Cheers
Steve, M0BPQ


Re: F6BVA 10 GHz transverter PCB group order

Dave G8KHU
 

Hi Neil
Please put me down for 3 boards
Thanks
Dave
G8KHU


Re: HERMES Lite 2

Andy G4JNT
 

In fact it grows faster than exponentially.   The rate of growth of number of sproggies is near-enough a factorial function of the number of frequencies (conversions) present.  Factorial being the fastest mathematical function there is - I think.

 The Inmarsat-3 satellite transponder - which went through its design phase in the late 1980s had multiple (reprogrammable) local oscillators to steer uplinks blocks of frequency to L-band blocks to allocate to spot beams, going via an IF in the VHF region to use SAW filters.   The sheer number of possible interactions that had to be thought about was horrific.  And computer processing power back then was orders of magnitude lower than it is now; some calculations of high order IMPs  took overnight on a PC of that era.  



On Fri, 29 Jan 2021 at 15:55, Chris Bartram G4DGU <chris@...> wrote:
I have a Hermes Lite 1 (essentially much the same as the HL2, but minus
much of the analogue I/O circuitry).  I built mine a few years ago with
the idea of using it as a microwave IF. Although with HB input filters
and QUISK it gave a pretty good account of itself on HF, the conversion
from the 28MHz region to the 144MHz IF of most of my transverters was
the deciding factor and I didn't take the project further.

Why? If there's one thing that the design of receivers for type-approved
use has taught me is to minimise the number of frequency conversions in
any system. Apart from the effect on dynamic performance, Frequency
conversion nearly always shows-up gotchas, and multiple conversion
shows-up multiple gotchas. These will often multiply exponentially and
oft-times can't be be easily designed-out. Also the acquisition of a
FDM-DUO transceiver at a very reasonable price finally made the decision
for me ...

I'm not suggesting that the HL1 or 2 are in any way junk. They're not! I
think the concept using the CATV modem chip and the FPGA design are
really neat. In the last few weeks I have been looking at my HL1
wondering what I could use it for. I have ideas, but I'm determined to
finish my current projects first!

73

Chris G4DGU







Re: round attenuator dissasembly?

John Fell
 

Ben,
I could be wrong , but when I opened up an O/C inline 1W rated pad from a junk bin  I found the sputter deposited /laser trimmed resistive elements had more or less vapourised .
However the R was deposited on thin ceramic substrate and that was retained along the long edges with what looked like Beryllium foil .Very tight /more or less impossible to get out without cracking the ceramic .
So basically do not cut/file or swallow the foil bits and you should live to enjoy the RF 'speriments you are doing .
73
John
G0API

On Fri, 29 Jan 2021 at 12:51, militaryoperator via groups.io <Military1944=aol.com@groups.io> wrote:
Take care Ben,
from their catalogue   Graham G3VKV

Most Aeroflex / Weinschel products contain beryllium oxide substrate. DO NOT sand, scrap or tamper with this substrate in any way. For more information about beryllium oxide or disposal, refer to the Material Safety Data Sheet or contact Aeroflex / Weinschel. 


They said:

Hello…. SN: BH2917 was MFR 8/04/1999 – unit is almost 23 years old.  This would be a non-repairable due to its age.
 With  Regards, Customer Relations Specialist, Weinschel.

As the small slice looks futuristic for 1999 I wonder how they fit them now?

So, have a nice cylindrical heatsink should  I need such !!

Ben


Re: F6BVA 10 GHz transverter PCB group order

 

Neil,
Can you please adjust my number to 3. (+1)
Thanks
Dave 
VE7HR 


On Jan 29, 2021, at 12:53 AM, Neil Smith G4DBN <neil@...> wrote:



Latest list of PCB requests. Cutoff time for board orders 20.00 this evening.Component orders no rush at all.

Neil G4DBN

Call PCBs Components
GI0GDP 2  
G4GLT 1  
G8AFC 1  
G0UHY 2  
G1YFG 1  
G4LDR 1  
G4DBN 5
 5 x full sets
G3ZQU 1  
G8JVM 1  
G3LYP 1  1 x FETs and Mixer
G4KNZ 1  1 x full set
G4DZU 1  
G3YGF 1  
GM8GAX 1  
G3GJA 2  
G4SHJ 1  
G7SOZ 1  
VE7HR 2  
G0OLX 1  
MM0FMF 1  

From: UKMicrowaves@groups.io <UKMicrowaves@groups.io> On Behalf Of Neil Smith G4DBN
Sent: 28 January 2021 21:48
To: UKMicrowaves@groups.io
Subject: Re: [UKMicrowaves] F6BVA 10 GHz transverter PCB group order

 

Sorry for the short notice, but Pierre-François is likely to close this group buy tomorrow, so if you would like to order some PCBs, please say so quickly! 

Don't worry about the components part of the order, plenty of time to sort that out, just let me know if you want a PCB. The price will probably fall a little as the volume increases, but the likely price is somewhere around £30 if we get stung for VAT and carrier ransom fee and duty. If Royal Mail are still operating by the time the boards arrive, I'll post them out first class large unless you are in one of the areas where they have given up trying, but again, we can sort that later on.

Details are at https://f6bva.pagesperso-orange.fr/Technique/trans%20uhf%20vers3cm/dossier%20print%20Ag%20complet.pdf

Once the boards arrive, I'll contact you for delivery info and let you know the final cost. Paypal or bank transfer or cheque are fine

Remember you need to provide a suitable local osc.  Read the info and the link that Daniel posted earlier. As mentioned, if you are not up to speed in French tech abbreviations, CI = PCB, CMS = SMD, OL = LO

This is the order so far. If I've missed you off or got the number wrong, or you need to change/cancel, please let me know before tomorrow night

Neil G4DBN

On Thu, Jan 28, 2021 at 12:35 AM Neil Smith G4DBN <neil@...> wrote:
If anyone in the UK is considering building an F6BVA 3cm to UHF transverter, there is a group purchase under way for the PCBs. To save on carrier fees, I am happy to receive boards for other UK purchasers and post them onwards. 

I have ordered three for myself. Price for the last batch worked out at 23€ plus postage, that was for 30 boards. There will be VAT, local postage, a share of the carrier fee and processing, and potentially UK duty to be paid (the silver plated PCBs are from a Chinese fab) so the final UK price might be over £30 each.

Read the updated tech info in the link below, and the earlier versions it links to. If you are not able to read technical French and rely on Google Translate, remember CI = PCB, OL = LO, CMS = SMD.

Neil G4DBN


From: f5bqp_Pierre-François MONET <pfmonet@...>
Subject: [hyperfr@...] Mise à jour de la Groupire CI Trvt 3cmBVA_batch7
Date: 27 January 2021 at 20:52:24 GMT
Resent-From: pfmonet@...
Bonjour,

La Groupire batch7 du CI du transverter 10GHz avance tout doucement puisque 18 exemplaires sont maintenant inscrits.
Le descriptif est ici:
https://f6bva.pagesperso-orange.fr/Technique/trans%20uhf%20vers3cm/dossier%20print%20Ag%20complet.pdf


HERMES Lite 2

Chris Bartram G4DGU
 

I have a Hermes Lite 1 (essentially much the same as the HL2, but minus much of the analogue I/O circuitry).  I built mine a few years ago with the idea of using it as a microwave IF. Although with HB input filters and QUISK it gave a pretty good account of itself on HF, the conversion from the 28MHz region to the 144MHz IF of most of my transverters was the deciding factor and I didn't take the project further.

Why? If there's one thing that the design of receivers for type-approved use has taught me is to minimise the number of frequency conversions in any system. Apart from the effect on dynamic performance, Frequency conversion nearly always shows-up gotchas, and multiple conversion shows-up multiple gotchas. These will often multiply exponentially and oft-times can't be be easily designed-out. Also the acquisition of a FDM-DUO transceiver at a very reasonable price finally made the decision for me ...

I'm not suggesting that the HL1 or 2 are in any way junk. They're not! I think the concept using the CATV modem chip and the FPGA design are really neat. In the last few weeks I have been looking at my HL1 wondering what I could use it for. I have ideas, but I'm determined to finish my current projects first!

73

Chris G4DGU


Re: F6BVA 10 GHz transverter PCB group order

Noel G8GTZ
 

1 PCB for me please.

 

73

Noel – G8GTZ

2141 - 2160 of 62970