Marconi Adret 742B RF signal generator

[DoricLoon]

Hi I've just purchased a Marconi Adret 742B RF signal generator. Can't seem to find a manual for it anywhere. The best I've managed is a French version for the 740. The cheet sheet attached to the generator lists sweep parameters and their memory locations.

Entering the first couple of sweep parameters start and stop frequency seems straight forward. The bit that has me foxed is how to set the "Frequency step and switching time by step" M92 in the case of band 1 sweep.

Does anyone have an English manual for this generator or just keypress sequence instruction for setting sweep parameters?

Thanks in advance

Jim

[Pinkus]

Yeah, it seems these Marconi generators are not very intuitive to use.
I had one too (even older than yours) without a manual. Eventually I found one and kept it on my hard drive as I was to lazy to delete it (the Marconi was sold a few years ago).
It is from a Marconi 2019A (80 Khz-1040 Mhz). Even this manual was hard to find a few years ago (maybe easy today .... or even harder).
Please PM me with your mail adress if you are interested and I can send it to you. At least it might help to get an idea about what to enter where.

[PA0PBZ]

Maybe you already found this, and it is only stating the obvious: http://midas.herts.ac.uk/helpsheets/signal%20generator.pdf

[Gyro]

Sorry, can't help you with the 742. I have the original paper manual for my Adret 730A.... and yes, it is in French - I don't think they ever bothered to do English translations.

[DoricLoon]

Sorry, can't help you with the 742. I have the original paper manual for my Adret 730A.... and yes, it is in French - I don't think they ever bothered to do English translations.

Thanks yeah i have the French operators manual for the 730 and 740. I also have the English version of the service manual for the 730 can send you it if you want?

Maybe you already found this, and it is only stating the obvious: http://midas.herts.ac.uk/helpsheets/signal%20generator.pdf

Yeah I also have that, unfortunately it's about all I can find regards the 742B.

However I have now figured out how to do sweeps 

For anyone who needs to know.

Enter frequency and amplitude for start frequency then key "M 9 0"
Enter stop frequency key "M 9 1"
Enter step frequency and then press the "FM" key enter step interval the key "M 9  2"

To run the sweep key "SPL" "9 0"

Hurray, works a treat. Only strange thing is, time is supposed to be mS and entering a max value of 1999 is stepping at more like 100mS

The FM key to allow entry of the time variable was the bit that foxed me. There is "step" below the FM key. All the other labels are above the keys. Therefore each time I pressed what I thought was the step key I was entering a modulation depth value.

If anyone does stumble upon a manual, even in French I'd appreciate a copy.

Thanks

Jim

[Gyro]

Thanks yeah i have the French operators manual for the 730 and 740. I also have the English version of the service manual for the 730 can send you it if you want?

Luckily I have a copy of the 730A service manual too (strange that should be in English but the User manual in French). Thanks for the offer though. 

Glad you got the sweeping figured out.

[Fraser]

I own an ADRET 740A RF signal generator. Lovely hand built quality, but the data entry did seem a bit querkie when compared to my other signal generators.

My unit came without user or maintenance manuals but I tracked them down in America and imported them. They were not cheap !

I attach pictures of what I have.

The 740A user manual is in English and the Maintenance manual has both French and English versions. I am fortunate to have the full set of schematics as well.

Fraser

[DoricLoon]

Hi Fraser,

You don't have details of the place where you managed to track down the manuals do you? I have the French version for the 740. It's what I have used as a reference. I also have the schematics for the 740 which won't be perfect for my machine but if the need arises it's better than nothing.

Next problem is to get Signal Hound SA44B and Adret 742B to track. Not so easy.

[Mr Helpful]

Are you still looking for manuals?

I may be able to help.

[Fraser]

If anyone in the UK wants one of these signal generators I will be selling mine.

PM me if interested

Fraser

[DoricLoon]

Are you still looking for manuals?

I may be able to help.

Between the manuals for the 740 and some playing around I have it pretty well sussed out now but if you have an documentation for the 742B I'd be glad to have a copy.

Thanks Jim

[jhl620]

I realize this topic hasn't been active, but I was hoping to find an answer about a Marconi / Adret 730A that I'm currently using, for which there doesn't appear to be a user manual anywhere that I can find. I did find the service manual, which is online but doesn't have the information I need. I'd love to get information about how to switch this instrument to remote control and the various IEEE488 (GPIB) codes. I saw that someone had posted a picture of a similar manual? Any chance to find out where you got it? Even the 740 manual might be helpful at this point! Thank you!

[Gyro]

Welcome jhl620 

You can find the 730a manuals at http://bama.edebris.com/manuals/adret/730a
They're a mixture of French and English as discussed earlier in the thread.

[DoricLoon]

I realize this topic hasn't been active, but I was hoping to find an answer about a Marconi / Adret 730A that I'm currently using, for which there doesn't appear to be a user manual anywhere that I can find. I did find the service manual, which is online but doesn't have the information I need. I'd love to get information about how to switch this instrument to remote control and the various IEEE488 (GPIB) codes. I saw that someone had posted a picture of a similar manual? Any chance to find out where you got it? Even the 740 manual might be helpful at this point! Thank you!

The link below should take you to my dropbox where I've uploaded a copy of the manual for the 730a. The manual includes instructions on remote access. That section is in French but those instructions and control strings are the same anyway.

https://www.dropbox.com/s/s2dmqtun7o9vyls/adret_730a_vhf-generator.pdf?dl=0

Below is a snip of code to ramp the frequency through steps from 1MHz to 500MHz in VBA with Visa. I'm no master coder so don't take it as gospel but example of the control strings are there.

Code: [Select]

Option Explicit

    Dim ioMgr As VisaComLib.ResourceManager
    Dim RFG As VisaComLib.FormattedIO488
    Dim AWG As VisaComLib.FormattedIO488
    Dim instrQuery As String
    Dim instrAddress As String
    Dim FRQ As Integer
   
   
   
Public Sub Initialize_Click()

On Error GoTo ioError
   
    Set ioMgr = New VisaComLib.ResourceManager
    Set RFG = New VisaComLib.FormattedIO488
    Set RFG.IO = ioMgr.Open("GPIB0::1::INSTR")
   
   
Exit Sub

ioError:
    MsgBox "An IO error occured:" & vbCrLf & Err.Description
   
End Sub
   

Public Sub cmdSetUP_Click()

On Error GoTo ioError

    RFG.WriteString ("*RST")
    RFG.WriteString ("F 1e6")
    RFG.WriteString ("A-30")
    RFG.WriteString ("FM0")
    RFG.WriteString ("RF 1")
   
   
   
    MsgBox "RFG set to 1MHz -30dBm  No FM modulation"
   
Exit Sub

ioError:
    MsgBox "An IO error occured:" & vbCrLf & Err.Description
   
End Sub

Public Sub Ramp_Click()


   
    For FRQ = 1 To 500
        On Error GoTo ioError
        RFG.WriteString ("F " & FRQ & "e6")
        Application.Wait (Now + TimeValue("0:00:02"))
       
    Next FRQ
   
Exit Sub

ioError:
    MsgBox "An IO error occured:" & vbCrLf & Err.Description
   
End Sub

Public Sub cmdReadIDN_Click()

On Error GoTo ioError
   
    instrQuery = AWG.ReadString
    MsgBox instrQuery, , "Instrument responce to *IDN?"
Exit Sub

ioError:
    MsgBox "An IO error occured:" & vbCrLf & Err.Description
   
End Sub


Public Sub instrclose_Click()

On Error GoTo ioError
   
    RFG.IO.Close
    MsgBox "Connection Closed"
Exit Sub

ioError:
    MsgBox "An IO error occured:" & vbCrLf & Err.Description
   
End Sub


[Ankorjd]

Hello,

The service manual for the ADRET 742 is uploaded in the KO4BB web site with 2 manuals (schematics and description of each module). What is missing are the schematics for the:
   - Output module 3
   - Attenuator control
   - Pulse modulation
   - Pulse driver

If some of you have these schematics we could have a complete service manual

Thanks in advance

Ankorjd

[e_pigreco]

Hi,
I know is a bit an old post, but it seems that also myself need help on the same Adret Signal Generator.

I am replacing some tantalums which seem to have exploded but I need a full manual with schema all the schemas. As said by other people the downloadable version is missing some boards.

Can someone help me to identify the values of the popped tantalums in the photo, just taken from my 742 device ?
I already changed the C716 tant on the amplifier output board which was exploded and now I found also these tantalums exploded and I think this is the Attenuator board.

[George Edmonds]

Hi

I have the final printed copy of the Adret manual from Marconi.  There is no schematics for the attenuator in it, it was very probably a factory exchange only item, just a parts list.  All Tantalum capacitors used are either 16uf or 22uf at 16VDC.  Suggest you up them all to a higher working voltage.

Have you changed the Saft Nicad backup battery on the CPU card, they all leak and damage/destroy the CPU card

George G6HIG in Dover UK.

[PerArdua]

Hi,
I know is a bit an old post, but it seems that also myself need help on the same Adret Signal Generator.

I am replacing some tantalums which seem to have exploded but I need a full manual with schema all the schemas. As said by other people the downloadable version is missing some boards.

Can someone help me to identify the values of the popped tantalums in the photo, just taken from my 742 device ?
I already changed the C716 tant on the amplifier output board which was exploded and now I found also these tantalums exploded and I think this is the Attenuator board.

I've checked on my 742A and it is a 10uF, 25V tant. If you're (or anyone else ) is around, could I ask for confirmation on the value/voltage rating of my blown resistor? 

Apologies for the necroposting, but I have a 742A which I suspect might be toast as there is some appalling soldering on this UHF board. Unfortunately no pics/schematics exist of this, and even worse I suspect the Adret 1226 modules (unobtanium) might be toast. Could anyone share a picture of their UHF boards please? In particular, looking to see if the trace (green circle) has been cut, and to determine whether the capacitor (orange circle) is original or not - I think I can see the remnants of a MLCC which drains away any further hope I have of easily repairing this.