g0ozs

You can still get the mounts from helmut-singer.de (http://www.helmut-singer.de/stock/1756077493.html) - if the mounting blocks are missing from the radio then Dave G8XUL has published a 3d printer model at https://www.thingiverse.com/thing:2680033 that cost him 29p to manufacture for me !

Iain

73 de G0OZS

I think it depends on who imported them - I once had BNT??K which was imported by the Gun bus company (later WH Bone) which is the other extreme.

the French “Charge Utile” magazine had a production history in a 3 part article (issues 87-89 from memory) which suggests trials in 1959 although the radiator grille looked quite different and series production of about 8000 units from 1961 through 1972 with mostly 3 tonne long wheelbase units after 1970. The bulk were delivered in large orders from 1964 to 1968.

this does not completely mesh with the serial numbers - the three I had were in the 13,000s, 14,000s and 17,000s so I guess they either made more for other customers or started from 10K rather than 1. There are some differences between early and late units if they still have all of their original parts - in particular later units have a 2-bar wing mirror support and rectangular rather than round mirrors. 

I suppose the only sure way to date a specimen is to have the tree rings in the wooden load bed dated by a dendrochronologist  

regards & seasons greetings 

iain 

Ps I have 2 rear body side panels (a bit rusty) left free of charge to take away  if anyone wants to collect them 

The heater current alone will be significant - I would expect for something of this period that the heaters are wired to run off the vehicle supply and the transistors will be a power oscillator driving the transformer for the high voltage supply (in preference to the mechanical vibrators used in 1940s sets).

It's worth turning the lights off when it is powered to check all the valves are glowing. I would expect for a set getting on for 60 60 years old that some components will have aged - the usual suspects are capacitors (both electrolytics and "Hunts" paper capacitors with a metal can that has a tag one end and a wire through a rubber bung the other end) gradually which become leaky   and carbon composition resistors which end up much higher than marked value. Disconnecting and testing these is generally a good idea.  Mechanical contacts in switches and potentiometers also tend to corrosion and go high resistance if disused, especially in cool damp storage.

You may find: 

https://www.vintage-radio.com/repair-restore-information/index.html

useful. 

Early germanium transistors suffer from various slow deterioration mechanisms unknown at the time they were made - both crystal growths on the surface in storage  electro-migration when in use. If the power inverter is not oscillating because of transistor failure then there will be no HT voltage even though the valves are lit. If it does have an inverter power supply using the transistors as I suspect, then the circuit is likely similar to a Heathkit HP-13 see: 

http://radionerds.com/images/3/3f/Portable_power_for_the_TCS-Roger_Basford_G3VKM.pdf 

As it has two fixed channels determined by the crystals either side of the relay at bottom right you will need to either find an airfield that uses those channels or use a signal generator instead - changing the crystals before it is otherwise working is unlikely to succeed because there are then too many unknowns 

Regards

Iain

FWD Roadless B4E1 

http://www.iwm.org.uk/collections/item/object/205212661

with a little help from Google

It may be my eyes but is there a badge on the radiator above the number plate that looks like

FWD 

in a top left to bottom right diagonal ? 

Regards

iain 

BCC was part of Daniel Prenn's Truevox group which merged into RACAL around 1970 becoming RACAL-BCC  - most of the "RACAL" Clansman sets are really BCC designs or descended from them - they represent a separate, parallel product line with BCC model numbers (even through to 1980s BCC39 Panther family secure radios)  to the RACAL Mobilcal subsidiary which made sets with RA or MA numbers for export. 

This looks quite early - probably around 1960. If the labels above and to the left of the  "Channel" switch are frequencies then 122.8 and 123.? MHz is consistent with air mobile or ground to air use. BCC transferred its aeronautical radio business to another Truevox group company before 1960 according to http://brenelltape.co.uk.websitebuilder.prositehosting.co.uk/truvox .

Regards

Iain

Now Sold

Dear All

As a result of a financial setback my Defender 90 is now on e-Bay as https://www.ebay.co.uk/itm/182919490301

If the successful buyer mentions finding it via HMVF I will of course make a contribution to the forum running costs!

Happy Bidding

Iain

Jerry

All intact SUMBs are 24v - there were 2 x 12v about 36ah batteries in a tray between the seats in the cab. The “FFR” ones that had radios in the back had a 2nd battery tray in the front left corner of the rear body and - at least in the one I worked on which had been “got at” - each battery was paralleled with the equivalent one in the cab battery box 

An. unmodified SUMB will also have a battery cutoff switch on the left side of the engine/gearbox tunnel in the driver’s footwell which is connected between chassis and the battery negative ( so battery negative is floating when the power is cut off)

there should be a 2-pin US style jump start/charging socket to the left of the drivers seat you can use to connect an external battery pack.

regards 

IAin

Assuming a radio is healthy the test switch can be turned to the "28V SPLY" position to confirm on the meter that there is a power input even if the radio is switched off.  I am not familiar with the CVRT installations but usually the radios in harness have at least 4 connections:

1) A 2 pin power lead from the DC input socket to a "LT Box" with anything from 1 to 15 2 pin power sockets - this will in turn be fed from a switchboard or direct from the battery. The 353 unlike the 321 does not have a user accessible input fuse but relies on the fuse in the LT box (I find a lot of LT boxes have blown fuses or have been robbed of fuses, as they come from Withams) . PTS Norfolk aka GTEN98 on E-Bay has the full range of fuses if that's all it is.

2) An audio connection from the "Harness" socket on the radio to a radio port on the "Interface Box" (IB2 or IB3)

3) A coaxial BNC cable to the ARFAT box

4) A control cable from the large ANT/ARFAT socket to the ARFAT box

As Bazz noted, with Clansman, unlike some older AFV radios, the intercom amplifier is in the Interface box so intercom works with no radios connected. All that "should" be necessary for intercom to work is power to the interface box and a ring of 12 pin harness cables linking all of the crew boxes to each other and the interface box.

|---CB2---CB2---IB2---CB2---CB2---|
|                                 |
|------DB-----------COMMANDER-----|
                         |
                        CPU

(This example is a 2 radio system with too many crew boxes)

It is also important to match the type of headgear and interface / crew boxes - the boxes should either be all gold fronted (new ANR boxes) or all black fronted (original). The black pressil boxes for the headset push to talk are used with the original type and the green pressil boxes are used with the ANR type (I think ANR are backward compatible with original but not 100% sure)

Regards

Iain

Also consider RAF Foxhall Heath (a WW2 RAF wireless site now the home of the Suffolk Aviation Heritage Society) and Landguard Fort / Felixstowe Museum (a WW1 and 2 coast defence battery) - there is also a radar museum at Bawdsey, site of the first operational Chain Home set and later an RAF Bloodhound missile site

Iain

Here are my photos from today’s event - nice weather, nice people and nice vehicles plus decent catering - looking forward to next year !

Iain

Likewise - Joris attached a screenshot when replying to my Avatars post that I can't see and if I click on it I get a "404 not found" error. I can see the Quad above though !

Another one that fails for me is FESM_NDT's australian finds post - the url that gets 404 error is:

http:\\hmvf.co.uk/topic/37688-australian-finds/<fileStore.core_Attachment%GT;/monthly_2017_10/20170916_110504.jpg.7f12768dfcdc8f999adb2e03fe881725.jpg

Comparing the pic of the quad that I can see the link code is:
http:\\content.invisioncic.com/hmvf/monthly_2017_10/quad01.jpg.54a4c427b2874a68c0cb93bb12254f65.jpg

I changed the initial // to \\ and the embedded left and right arrows to < and > so the link code displays in the post

Iain

Joris

Thanks - now done. As an aside the screenshot doesn't display and I get 404 not found if I click on it.

Regards

Iain

Hi

I would have opened a support ticket but "that feature is not available to my account" yet, and the answer may anyway be useful to more than me so I will post it here where it's searchable. I see some users have correct sized avatar images of their choice beside their names, but others have an initial letter of their forum username in a circle - "G" in my case. I have tried uploading a picture but that hasn't appeared as an avatar - a larger version appears if I hover the mouse pointer over the "G". I can't see a way in the "profile" or "account" settings to do so - is it one of those things that have been migrated but aren't yet available to edit ?

Thanks

Iain

I have had things from them in the past but didn't get a reply last time I asked for pricing on something (late last year as I recall) - for Clansman kit I concur with the recommendations of ta_shuntca_uitco, Steve Slack and PTS Norfolk.

These are Clansman specialists - for Russian and NATO radios I have used radiosurplus.it, https://www.sparks-military.com/en/, and http://www.reforger.de/en/18-us-army-military-radio- this year with success - TDM Electronics in Poland sometimes have good prices and sometimes not, as well.

Iain

Welcome here !

Iain

Hi

To get the total resistance needed for a given full scale deflection (FSD) we use ohms law

R = V / I where V is the FSD voltage on the scale and I is the current needed by the meter (which is in reality current operated)

We know from the scale that this meter has a resistance of 400 ohms and a lower range of 6V, so changing the subject of the formula

I = V/R = 6/400 = 0.015 = 15ma

The total resistance needed for 15ma at 60v is

R = V/I = 60/0.015 = 4000 Ohms.

Since the meter itself has a resistance of 400 ohms we need to add 3600 ohms (3.6K) in series with the meter as a "multiplier" to make up 4000 ohms.

As a sanity check, the less scientific approach is to say that as the FSD current is a physical property of the meter, and to get the same current at 60V as at 6V requires a resistance 10 times higher, and as the meter is marked 400 ohms, the 60V range should need 400 * 10 = 4000 ohms.

Hope this helps

Iain

PS the original post already confirms that the 6V range is accurate without a series resistor, so we can calculate it as 6V / 400 ohms. Otherwise there would be no way to know the full scale current unless it is printed on the meter. Anyone else reading this who has an unknown voltmeter should be careful testing without a series resistor in case it was designed to use an external one - best to start with a reasonably high value (around 20,000 ohms in series per volt of scale is needed to protect a 50 microamp movement) and reduce it until the meter reads full scale at the correct voltage, and then work out or measure the FSD current.

My daughter's Ju-Jitsu class has changed to Tuesdays so dad's taxi is needed elsewhere now so apologies for this and next month, at least - Iain

Thanks. Tuesday evenings should be free for the next two months - I recognise a few of the owners on your page and I think Jack's landrover is younger than mine

Iain

Hi

I really must join - although my landrover 90 may be a bit modern for MVT now I no longer have the SUMB ?

@ Lozzaboy: as an aside I must be within yards of you (on A140 just south of Brockford BP filling station!)

@ N.O.S: What evenings are the meetings at the RBL ?

Iain

Welcome to the forum ! I have some Clansman info at http://www.g0ozs.org/clansman which may help, it's also worth joining the WS19 group (http://www.royalsignals.org.uk) or VMARS to get access to an archive of the installation and service manuals

Regards

Iain

Hi

I used to have a 15 foot ridge tent (I think properly called a 160lb patrol tent) that was as big as the 12x12 (if a little less headroom at the sides) but I could safely put it up on my own with a little difficulty - with a second person for 5 minutes it was easy. See: http://www.g0ozs.org/clansman/GB2CRF/subalbum_1.html - It did of course need soft ground for all the guy pegs - the 9x9 and 12x12 are more use to me doing radio events sometimes on paved ground. It also sheds water better in a downpour than the frame tents (my 12x12 with its original canvas tended to have pools along the inside of the eaves - we got soaked at the last Ashford W&P when there was downpour the last night - I believe a liner and support straps are needed to prevent that).

As an aside the 12x12 with a new roof canvas from Anchor is still on e-bay item no. 182694381814 if you do decide on the 12x12 solution - I will be reducing the minimum offer accepted if it doesn't go by Monday ..

Regards

Iain

Gordon

I will need to try and work out the ratio from the DC resistance next time I have one on the bench - based on my attempts at cutting elements to length I think it is around 3:1 or 4:1 - possibly an auto transformer because the impedance at resonance is far too low. It is easily bypassed by moving the connection for the antenna base pigtail from the transformer directly onto the BNC pin. The elements are still slightly shorter than expected after that, because the pigtail acts as almost a 1 turn call.

Regards

Iain

Martin

If it helps I have two cookers No. 2 in need of refurbishment - an incomplete Mk 2 and a complete Mk 1 - neither pressurises when pumped so probably new seals needed all round. I also have a set of aluminium utensils. PM me to discuss price & postage if interested - I want the cubic feet back rather than a large price !

Iain

I am after a no 2 cooker for my Daimler dingo, anyone got one they don't need.